layout: restructure into src/ tests/ android/ scripts/ tools/

- extension/src/{port,platform,codepage} -> src/; native_render -> src/host
  (+ dxt, shaders/); libgr2 -> src/gr2; extension/third_party -> third_party
- extension/tests -> tests/port, libgr2/tests -> tests/gr2
- android-native -> android (build.sh, push-client.sh moved in)
- script -> scripts; tools/40250 -> tools/server; oracle -> tools/granny-oracle;
  perf tools -> tools/perf
- all build trees under build/ (native, release, android, port-gate)
- xrender:: CMake aliases -> mt::; port-map ledger impl paths rewritten

No code changes. ctest 15/15, port_gate macos+android PASS, port_map check 0 errors.

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

CLAUDE.md

@@ -1,5 +1 @@
-# Project instructions
-
-For any Metin2 40250 comparison, 1:1 parity, missing original-client behavior, or parity-regression task, use the project skill `metin2-40250-parity-audit` from `.claude/skills/`. Keep audit state in `audit/manifest.json`; do not repeat still-valid verified work.
-
-The current port route, decisions and cross-machine setup are in `docs/PORT-PLAN.md`; read it first when resuming port work.
+@AGENTS.md