Initial scaffold: open-memory plugin for OpenCode

- Plugin entry point with hooks: experimental.session.compacting,
  experimental.chat.system.transform, event
- Context tracker: SSE-based token tracking per session with
  green/yellow/red/critical thresholds
- Tools: memory_context, memory_compact, memory_summary,
  memory_sessions, memory_messages, memory_search, memory_plans
- History module: sqlite3 queries + markdown rendering
- Compaction: improved prompt emphasizing self-continuity
- Research docs: ARCHITECTURE.md + opencode-memory reference

tsconfig.json

@@ -0,0 +1,18 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "module": "ES2022",
+    "moduleResolution": "Bundler",
+    "types": ["node", "bun"],
+    "strict": true,
+    "noEmitOnError": true,
+    "declaration": true,
+    "emitDeclarationOnly": true,
+    "outDir": "dist",
+    "rootDir": "src",
+    "verbatimModuleSyntax": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true
+  },
+  "include": ["src"]
+}