chore(meta): update changelog for sprint 9 client work

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CHANGELOG.md

@@ -7,6 +7,9 @@ Format based on [Keep a Changelog](https://keepachangelog.com/).
 ## [Unreleased]
 
 ### Added
+- Client P2 tests (#492) — 16 gdUnit4 tests for camera (smoothing, zoom, viewport, follow, no-pan), entity alpha/color (peripheral, forward, NPC color, player constant), UI (monologue, interaction, inventory, dialogue, pause, fog blob, fog z_index)
+- Client P3 tests (#493) — 12 gdUnit4 tests for z-layer ordering (floor/ysort/fog/UI), entity lerp (snap, converge, LERP_SPEED=12.0), Tyre additions (recognition, facing, delta scaling, blob removal)
+- Anti-tedium regression tests (#494) — 5 tests: F12 no-crash guard, no queued input, gauntlet UI hidden in default/normal snapshot/multi-tick modes
 - Protocol v8: dialogue_response field decoding (DialogueResponseEvent with line_id, text, speaker_entity_id) from server #305/D-028
 - Test client binary scaffolding (#480) — standalone crate at `tooling/test-client/` with CLI (--connect, --replay, --text, --json, --quiet, --golden, --ticks), exit codes (0/1/2), golden file JSON diff, JSONL replay loader
 - Snapshot text renderer (#481) — `format_snapshot_text(&ObserverSnapshot)` pub-exported from server crate, entity labels as kind:entity_id sorted by distance, room name stub, 10 unit tests
@@ -15,6 +18,7 @@ Format based on [Keep a Changelog](https://keepachangelog.com/).
 - Stance change audio (`sfx_stance_change.ogg`) — subtle mechanical click for stance toggle feedback (#440)
 
 ### Fixed
+- MessagePack int_64 encoder dead code branch (#516) — `-(1 << 63)` overflowed making int_64 branch unreachable; negative values beyond int_32 now correctly encode as 0xd3 instead of 0xcf
 - Protocol version bumped from 7 to 8 to match server — fixes 5 test failures from version mismatch
 - Interact action encoding changed from unit variant to struct variant to match server's PlayerAction::Interact { target_entity_id, verb }
 - Monologue duplication test (test_monologue_not_duplicated_after_consumption) fixed — was using poll_snapshot() which doesn't consume _last_snapshot in test mode