Merge branch 'claude/hopeful-darwin-ae8b87' — Phase A.5 SHIP + Quality Preset system
Phase A.5 — Two-tier Streaming + Horizon LOD shipped.
Headline: 2.3 km terrain horizon (radius=4 near + 12 far) with off-thread
mesh build, fog blend at N₁, mipmaps + 16x AF, MSAA 4x + A2C foliage,
depth-write audit, BUDGET_OVER diag, Quality Preset system (Low/Medium/
High/Ultra) with env-var overrides + F11 mid-session re-apply.
~999 tests pass, 8 pre-existing physics/input failures unchanged.
Two structural-to-A.5 bug fixes shipped post-T26:
- Bug A (9217fd9): far-tier worker strips entities (T13/T16 had only
wired the controller side; far-tier was loading full entity layers,
~71K entities instead of ~10K, 5x perf regression).
- Bug B (0ad8c99): WalkEntities scratch list reused across frames
(was 480 KB / frame allocation).
Tier 1 entity-classification cache attempted as polish (3639a6f),
reverted (9b49009) — broke animation by caching mutable per-frame
state. Retry deferred to post-A.5 polish phase (ISSUE #53).
Deferred to post-A.5 polish:
- Tier 1 retry with animation-mutation audit (ISSUE #53)
- Lifestone missing visual (ISSUE #52)
- JobKind plumbing through BuildLandblockForStreaming (ISSUE #54)
- Tier 2 (static/dynamic split) + Tier 3 (GPU compute cull) —
separate multi-week phases. Roadmap at
docs/plans/2026-05-10-perf-tiers-2-3-roadmap.md.
SHIP commit: 9245db5.
d3d78fa14f