cleanup: remove Godot-era test data, formats/, dead proto reader and duplicates

- test/: bgfx/Godot render goldens and compare shots nothing reads any more;
  the Granny oracle result m2-numeric.json moves to oracle/
- formats/: only the .spt sniffer was still linked; it moves into
  platform/SpeedTreeLib, the rest and tools/map_probe go
- bgm/ duplicated Client/BGM byte for byte; tools/root archived root scripts
  that root.epk already holds; extension/src/proto had no build reference
- GEMINI.md duplicated AGENTS.md

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.gitignore

@@ -24,12 +24,7 @@ __pycache__/
 *.pyc
 .env.live-smoke.local
 
-# playable network tests: local scenario/fixture configs, credential files and
-# run outputs never enter git. Only scenario.example.json and the static gate
-# fixtures in test/playable are committed. Run outputs live under /build/playable.
-/test/playable/*.local.json
-/test/playable/*.local.txt
-/test/playable/runs/
+# credential files never enter git.
 *.credentials
 *.credentials.json
 .env.*.local
@@ -44,17 +39,8 @@ __pycache__/
 /oracle/*.dylib
 
 # vendored-lib test artifacts
-/test/oracle_dumps/
-/test/*.actual.png
 /build-tools/
 
-# libgr2 tool outputs
-/fuzz-report.json
-/test/m2-numeric.json.tmp
-
-# compare.py render output
-/test/compare-shots/
-/test/compare-report.json
 
 # Written by 40250 uitaskbar.py at runtime.
 /mouse.cfg