fix(bridge): align Extension protocol with Bot — 3 mismatches fixed

- Snapshot: response/chat_snapshot.txt → chat_snapshots/*.json
- Command field: cmd.message → cmd.text (matches Bot.write_command)
- RPC: GetConversation (404) → GetCascadeTrajectorySteps
- Bundle sql-wasm.js + sql-wasm.wasm into VSIX (45KB→379KB)
- Handle consumed flag, clean 38 stale commands
- Add extractAIText helper with fallback chain

docs/devlog/2026-03-08.md

@@ -0,0 +1,5 @@
+# 2026-03-08 Devlog — Bridge 프로토콜 수정
+
+| # | 시간 | 작업 | 커밋 | 상태 |
+|---|------|------|------|------|
+| 1 | 01:00 | Extension↔Bot 프로토콜 불일치 3건 수정 + sql-wasm 번들링 | `e4dc1b1` | 🔧 |