Add HeXi bot codebase: custom plugins, web frontends, tests

- hexi core: message handling, rate limiting, cooldown, plugin manager
- Custom plugins: BF stats, daily check-in, quotes, persona cards, etc.
- Community plugins vendored under hexi/plugins with local fixes
- Web admin frontends (learning-chat, persona-admin), unified hexi/web
- Tests for rate_limit/cooldown/memes/persona; poetry.lock

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

hexi/web/tsconfig.json

@@ -0,0 +1,22 @@
+{
+  "compilerOptions": {
+    "target": "ES2020",
+    "useDefineForClassFields": true,
+    "lib": ["ES2020", "DOM", "DOM.Iterable"],
+    "module": "ESNext",
+    "skipLibCheck": true,
+    "moduleResolution": "bundler",
+    "allowImportingTsExtensions": true,
+    "resolveJsonModule": true,
+    "isolatedModules": true,
+    "moduleDetection": "force",
+    "noEmit": true,
+    "jsx": "react-jsx",
+    "strict": true,
+    "noUnusedLocals": false,
+    "noUnusedParameters": false,
+    "noFallthroughCasesInSwitch": true
+  },
+  "include": ["src"],
+  "references": [{ "path": "./tsconfig.node.json" }]
+}