fix(chargen): Campaign CC CC7 review fix round — F1-F9 — REVIEW-CLOSED

Both dual-lens reviewers of `9cf6c522`+`ddcbf1fb` returned PASS-with-items.
This round closes all nine findings:

F1 files AP-229 for the screen-layering divergence (retail destroys/
reconstructs the current UI framework via UIFlow::UseNewMode; acdream
keeps both CharacterManagementUiController and CharacterCreationUiController
mounted for the whole lifetime and reveals/occludes) plus its narrow
residual risk (the shared RetailDialogFactory can hand UiRoot.Modal to a
dialog opened by the still-ticking, occluded management screen on an
inbound CharacterError) and what already matches retail (selection/
world-name persistence, click-through isolation, one coherent Modal
stack).

F2 rewrites the connected-gate script's roster-full step with the exact
`@modifylong max_chars_per_account` recipe and the pending-delete-counts
note. F3 adds AP-221's console-diagnostic lines to the known-gaps
paragraph. F4 adds an empty-name/AP-227 step. F9 notes that a uniform
Random pick over 13 heritages can repeat.

F5 adds an App-layer source-text pin
(GameWindowLiveSessionOwnershipTests.LiveSessionRuntimeFactoryBinds
CharacterCreatedAndCreationFailedToTheStatusWriter) for the delegate
wiring the reviewer proved was deletable without breaking any test — no
practical seam exists to construct LiveSessionRuntimeFactory without a
GameWindow, so this follows the file's own established source-text-pin
pattern; the payload shape is already pinned separately at
SessionStatusWriterTests.

F6 corrects the CC7 ledger's checksum-assertion wording (it is a
round-trip purity check, not an independent golden — the golden is
CharacterCreateTests.ComputeChecksum_ExactRetailAccumulationSet) and
cross-references it from the test's own doc comment.

F7 corrects the CC7 ledger's fixture-ordering claim (it had chargen
constructing first, backwards from RetailUiRuntime.Tick's real
management-then-chargen order) and reorders CharacterScreensFixedCanvas
ArbiterTests to match production, adding ClickThrough/ZOrder assertions
that pin the occlusion the reviewer previously verified only by hand.

F8 records a known flake (RuntimeCollisionReportingStateTests.
WarmedSteadyContactRefreshDoesNotAllocate, allocation-assertion load
sensitivity, pre-existing) seen under full-solution parallel load on
both reviewer runs.

Campaign status: all seven slices (CC1-CC7) are REVIEW-CLOSED; the
campaign is CODE-COMPLETE pending the user's own connected gate.

Runtime 1735/0 (unchanged), App 5257/3 skips (+1: the new F5 pin).
Full Release build: 0 warnings, 0 errors.

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

tests/AcDream.Runtime.Tests/Session/LiveSessionControllerCharacterCreationTests.cs

@@ -430,10 +430,22 @@ public sealed class LiveSessionControllerCharacterCreationTests
     /// test above never checked — against exactly the shape
     /// <c>CharacterCreateInfo.Unpack</c>/<c>Appearance.Unpack</c> parse (see
     /// <see cref="CharacterCreate"/>'s own doc comment for the ACE
-    /// cross-reference). The checksum is recomputed via the SAME production
-    /// <see cref="CharacterCreate.ComputeChecksum"/> formula rather than
-    /// re-deriving the sum a second time by hand in the test.
+    /// cross-reference).
     /// </summary>
+    /// <remarks>
+    /// Campaign CC CC7 review-fix round, F6 (2026-08-16): the checksum
+    /// assertion below (<c>Assert.Equal(CharacterCreate.ComputeChecksum(r),
+    /// decoded.Checksum)</c>) is a ROUND-TRIP/PURITY check, not an
+    /// independent golden — it recomputes the SAME production
+    /// <see cref="CharacterCreate.ComputeChecksum"/> formula the encode side
+    /// already used, rather than re-deriving the sum a second time by hand,
+    /// so it proves the wire-encode/decode round trip is lossless but
+    /// cannot by itself catch a bug shared by both the encoder and this
+    /// formula. The checksum's actual golden value (the 19-term retail
+    /// accumulation set, hand-summed to <c>205u</c>) is pinned separately
+    /// at <c>CharacterCreateTests.ComputeChecksum_ExactRetailAccumulationSet</c>
+    /// (<c>tests/AcDream.Core.Net.Tests/Messages/CharacterCreateTests.cs</c>).
+    /// </remarks>
     [Fact]
     public void Finish_SendsEveryWireFieldByteExactAgainstACEsUnpackShape()
     {