docs: A7.L1 session bookkeeping — close #190, update #93/#189, file #191

- #190 (interior entity id overflow) moved to Recently closed with full
  evidence trail — found + fixed same session as #189's investigation.
- #189 (missing particles) updated: root cause was #190's id aliasing,
  not the light-carrier hydration fix itself; fix shipped but the
  fountain's water spray hasn't been re-confirmed visually yet (session
  moved to an FPS question, then a movement bug, before circling back).
  The "candle" identification sub-thread stays open regardless.
- #93 (indoor lighting umbrella) updated earlier this session with the
  two A7.L1 root causes + fixes; #80/#94 still need re-verification
  before it can close.
- #191 filed: tapping W briefly glides forward without playing the step
  animation (retail: single visible step). Different subsystem
  (movement/animation, not rendering) — not investigated this session,
  filed to keep it from interrupting A7 lighting/particle work.
- Roadmap Phase A7 progress note added earlier this session.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

docs/ISSUES.md

@@ -46,6 +46,102 @@ Copy this block when adding a new issue:
 
 ---
 
+## #189 — Ambient particle scripts (fountain water, possibly candle flames) don't render indoors
+
+**Status:** 🟡 LIKELY FIXED (`e651cb6d`, #190) — pending final user visual re-confirmation
+**Severity:** MEDIUM
+**Filed:** 2026-07-09
+**Component:** rendering — particles / PhysicsScript
+
+**Description:** In the Town Network fountain room (`0x00070144`), the fountain
+has no visible water-spray particle effect. User also reported missing candle
+flames in the same area (unconfirmed which object(s) those are — see Root
+cause below).
+
+**Root cause / status:** NOT the A7.L1 mesh-empty hydration gate itself
+(`EntityHydrationRules.ShouldKeepEntity`) — directly refuted via dat-truth
+(`Issue93TownNetworkFountainRoomLightInspectionTests.
+FountainAndCandleSetup_DefaultScriptAndMeshSurvivorCount_Dump`): the fountain's
+Setup (`0x02000AA3`) has a surviving mesh part (not dropped) AND a real
+`DefaultScript.DataId = 0x33000B21` (almost certainly the water-spray
+PhysicsScript) — hydration itself was fine.
+
+**Found instead (via revert-test, per user request): #190, an entity-id
+overflow the light fix triggered as a SIDE EFFECT.** The mesh-carrier fix
+kept ~394 more entities alive per landblock, pushing the Town Network's
+interior-entity counter from 248 to 277 — past the id scheme's 8-bit budget
+(`ACDREAM_DUMP_ENTITY=0x02000AA3` showed the fountain's `entity.Id` shift from
+`0x400007F8` to `0x40000815`, misdecoding as landblock Y=0x08 instead of the
+true Y=0x07). `EntityScriptActivator` keys script/particle tracking on
+`entity.Id` directly, so the aliased id broke the fountain's script tracking.
+Fixed by `#190` (widened the id counter 8→12 bits). Post-fix,
+`ACDREAM_DUMP_ENTITY` confirmed the fountain's id (`0x40007115`) decodes
+correctly again — **not yet re-confirmed visually by the user** (session moved
+on to an FPS question, then a movement bug, before the fountain was re-checked).
+
+The guessed "candle" objects (`0x02001967`, 16 arranged around the fountain)
+turned out to have real mesh and `DefaultScript == 0` — they are NOT candles
+and carry no script at all, so the actual candle-flame source objects are
+still unidentified; that part of this issue stays open regardless of #190.
+
+**Next steps:**
+1. Get the user's visual confirmation that the fountain water spray is back.
+2. Identify the real candle-flame source objects in this room (not
+   `0x02001967`) before assuming they share a root cause with the fountain.
+
+**Files:**
+- `src/AcDream.App/Rendering/Vfx/EntityScriptActivator.cs`
+- `src/AcDream.Core/World/InteriorEntityIdAllocator.cs` (the #190 fix)
+- `src/AcDream.App/Streaming/GpuWorldState.cs` (DefaultScript fire/stop sites)
+- `src/AcDream.Core/Vfx/ParticleHookSink.cs`
+- `tests/AcDream.Core.Tests/Rendering/Issue93TownNetworkFountainRoomLightInspectionTests.cs` (dat-truth apparatus, reusable)
+
+**Acceptance:** The Town Network fountain shows a water-spray particle effect
+matching retail; candle/torch flame sources in the same room are identified
+and render correctly.
+
+---
+
+## #191 — Tapping W (brief forward press) glides forward without playing the step animation
+
+**Status:** OPEN
+**Severity:** MEDIUM (visible every time a player taps instead of holds a movement
+key — likely a common input pattern)
+**Filed:** 2026-07-09
+**Component:** physics / animation — movement input, motion sequencing
+
+**Description:** User-reported (live testing, unrelated to tonight's A7 lighting
+work): tapping W briefly translates the player forward smoothly ("glide") without
+the walk/run step animation playing. In retail, a brief tap produces a single
+visible step (a short animated motion), not a silent slide. Not investigated this
+session — filed to keep A7 lighting/particle work from being interrupted by an
+unrelated subsystem (movement/animation, not rendering).
+
+**Root cause / status:** UNKNOWN. Likely candidates for a future session (grep
+named retail decomp FIRST, per the mandatory workflow — do not guess):
+- The R5 movement-manager arc shipped 2026-07-05 (`docs/research/2026-07-03-r5-managers/`)
+  — check whether this is a regression from that work or a pre-existing gap it
+  didn't cover.
+- Retail likely distinguishes a brief key tap (press+release before some
+  threshold) from a held key at the INPUT/COMMAND layer, producing a distinct
+  one-shot "step" motion command rather than the continuous Walk/RunForward
+  cycle — search `docs/research/named-retail/acclient_2013_pseudo_c.txt` for how
+  `CMotionInterp`/the movement command dispatch handles a short-duration
+  ForwardCommand before it's promoted to a full walk/run cycle.
+- Candidate files: `src/AcDream.App/Input/PlayerMovementController.cs`
+  (local input → command translation), `src/AcDream.Core/Physics/MotionInterpreter.cs`
+  / `AnimationSequencer.cs` (cycle selection/dispatch).
+- Cross-reference `references/holtburger/crates/holtburger-core/src/client/movement/`
+  for what a real client sends on a brief tap vs a hold.
+
+**Files:** Not yet identified beyond the candidates above.
+
+**Acceptance:** A brief W tap produces a single retail-faithful step animation
+(not a silent glide); holding W still transitions normally into the walk/run
+cycle.
+
+---
+
 ## #187 — [DONE 2026-07-08] Non-hinged doors (sliding doors, gates) don't play their open animation
 
 **Status:** CLOSED 2026-07-08 — user-confirmed live gate: "sliding doors now work."
@@ -3198,22 +3294,49 @@ Retail oracle for cell-id hysteresis: `acclient_2013_pseudo_c.txt:308742-308783`
 
 ## #93 — Indoor lighting broken (M1.5 lighting umbrella)
 
-**Status:** OPEN — **M1.5 scope (A7 lighting fidelity, primary lighting issue)**
+**Status:** OPEN — **M1.5 scope (A7 lighting fidelity, primary lighting issue)**. Two real
+root causes found + fixed 2026-07-09 (A7.L1), user-confirmed improvement at the Town
+Network fountain room ("lightning is better"). Not closing outright — the umbrella covers
+several symptom classes (#80 2nd-floor darkness, #94 held-item spotlight direction) that
+weren't re-verified this session, and #189 (missing ambient particles, found in the same
+room) shows there's more to the "feels right" bar than point lights alone.
 **Severity:** HIGH (degrades indoor experience; M1.5 acceptance depends on it closing)
 **Filed:** 2026-05-20
 **Component:** lighting, rendering
 
 **Description:** Interior cells (inn, cottages, dungeons — anywhere with `cellLow >= 0x0100`) render with lighting that doesn't match retail. Specific symptoms include #80 (2nd floor goes dark), wrong per-cell ambient, missing cell-internal light sources (torches/lanterns), and outdoor day-cycle bleeding into indoor cells. Umbrella issue covering the family; sub-issues to be filed during A7.L1 probe spike.
 
-**Root cause / status:** Suspected family of bugs in (a) per-cell environment-light tag parsing from the dat (we may not parse `cell.envLightInfo` correctly), (b) cell-light association (which lights belong to which cell), (c) indoor visibility culling for lights, (d) the indoor branch of `GameWindow.UpdateSunFromSky` which uses a flat ambient. Investigation deferred to A7.L1.
+**Root cause / status:** Two DISTINCT root causes confirmed + fixed 2026-07-09 for the
+Town Network "fountain room too dark" symptom (#79/#176/#177's deferred light-cap arc):
+1. **Candidate-pool starvation in dense hubs** (`d275ed55`): `LightManager.BuildPointLightSnapshot`
+   sorted ALL registered lights by raw player-distance with no visibility filter — in a
+   463+ fixture hub, geometrically-closer-but-wall-disconnected fixtures could out-rank a
+   visible room's own (farther) torches for the 128-cap. Fixed by scoping candidacy to
+   last frame's rendered visible-cell set (`RetailPViewFrameResult.DrawableCells`, one
+   frame of latency — see AP-85 in the divergence register for why this specific approach
+   was chosen over re-threading a mid-`DrawInside` callback, the exact mechanism that
+   caused the earlier c500912b #176 regression).
+2. **THE actual fountain-room darkness (`9ebb2060`, the bigger fix):** the mesh-empty
+   hydration gate (`GameWindow.cs` ~7324) dropped an entity's WHOLE registration — including
+   its `Setup.Lights` — whenever its visual mesh flattened to zero parts (a common dat
+   pattern: a "light attach point" Setup whose sole visual part is a legitimately
+   runtime-hidden marker, #136-class). Confirmed via direct dat-truth inspection
+   (`Issue93TownNetworkFountainRoomLightInspectionTests`): the fountain room's ONE
+   dat-authored light (a ceiling fixture, Setup 0x02000365) was silently dropped this way —
+   the room registered ZERO lights of its own, so scoping fix #1 alone had no local light
+   to redistribute. Fixed via `EntityHydrationRules.ShouldKeepEntity` — an entity survives
+   hydration if it has mesh OR lights, not just mesh. Dungeon-wide effect: registered
+   lights jumped 498→892 on the same launch.
 
 **Files:**
-- `src/AcDream.App/Rendering/GameWindow.cs:8330+` (`UpdateSunFromSky`, indoor branch with flat ambient)
+- `src/AcDream.Core/Lighting/LightManager.cs` (`BuildPointLightSnapshot` visible-cell scoping)
+- `src/AcDream.App/Rendering/GameWindow.cs` (hydration gate, `_lightPoolVisibleCells`)
+- `src/AcDream.Core/Meshing/EntityHydrationRules.cs` (the mesh-empty-but-has-lights predicate)
+- `src/AcDream.App/Rendering/GameWindow.cs:8330+` (`UpdateSunFromSky`, indoor branch with flat ambient — unrelated, unchanged)
 - `src/AcDream.App/Rendering/Shaders/mesh_modern.frag` (per-pixel light evaluation)
-- `references/WorldBuilder/...` (any WB lighting helpers we inherit)
-- Retail oracle: grep `Render::lighting_*` in `acclient_2013_pseudo_c.txt`
+- Retail oracle: grep `Render::lighting_*` / `add_light` in `acclient_2013_pseudo_c.txt`
 
-**Acceptance:** Holtburg inn interior lighting matches retail at the same character position. Holtburg Sewer dungeon torchlight reads correctly per-room. 2nd-floor cells brightness matches ground floor.
+**Acceptance:** Holtburg inn interior lighting matches retail at the same character position. Holtburg Sewer dungeon torchlight reads correctly per-room. 2nd-floor cells brightness matches ground floor. **Remaining before this can close:** re-verify #80 (2nd floor) and #94 (held-item spotlight direction) specifically — neither was re-checked this session; the Town Network fix targeted the starvation/hydration-drop symptom, not every #93 sub-symptom.
 
 ---
 
@@ -7278,6 +7401,34 @@ outdoors at the angle that previously erased it.
 
 # Recently closed
 
+## #190 — Interior entity id counter overflowed past its 8-bit budget, aliasing into the next landblock
+
+**Status:** DONE (2026-07-09, `e651cb6d`). Found while investigating #189
+(missing fountain particle): a user-requested revert-test of the A7.L1 light
+fix (9ebb2060) made the fountain work again, which didn't fit the earlier
+dat-truth finding that the fountain's own entity was untouched by that fix.
+Traced with `ACDREAM_DUMP_ENTITY`: the fountain's hydrated `entity.Id` shifted
+between reverted (`0x400007F8`) and fixed (`0x40000815`) builds — the extra
+mesh-less light carriers the A7.L1 fix now keeps alive earlier in the same
+landblock's hydration pass shifted `localCounter`. `0x40000815` decodes as
+landblock Y=0x08 — NOT the Town Network's true Y=0x07 — the exact `#119`
+cross-landblock id-aliasing bug, reincarnated by entity COUNT (277, past the
+8-bit/256 budget) rather than a computation bug; the `#119` fix's own comment
+had explicitly flagged this as a residual risk ("counter overflow past 0xFF
+still bleeds into the lbY byte"). `EntityScriptActivator` keys particle-script
+instances by `entity.Id` directly (no landblock-hint disambiguation, unlike
+`#119`'s Tier-1 batch cache), so the aliased id silently broke the fountain's
+script tracking. Fix: `AcDream.Core.World.InteriorEntityIdAllocator` widens the
+counter 8→12 bits (256→4096) by shrinking the fixed class-prefix from a full
+byte (`0x40`) to its top nibble (`0x4_`) — verified safe against every
+`entity.Id` classification check in `GameWindow.cs` (none decode X/Y back out,
+only threshold/prefix checks). Added a loud one-time `[id-overflow]` log if a
+landblock ever exceeds the new budget. Post-fix: fountain's id (`0x40007115`)
+decodes correctly (Y=7, counter=277, safely under 4095). Core 2675+2skip /
+App 741+2skip / UI 425 / Net 385 green.
+
+---
+
 ## #170 — Remote creature chase+attack renders wrong vs retail (glide, run not sustained)
 
 **Status:** DONE (2026-07-04, user visual gate passed — "as close to retail now as