chore: codebase audit — remove dead code, unused deps, clean configs

Phase 1: Delete 19 dead component/service/tool files (4,200+ lines)
Phase 2: Remove 13 unused npm packages (Radix UI, shadcn utilities, ytdl-core, etc.)
Phase 3: Database schema — drop agent_delegations, add performance indexes
Phase 4: Remove 12 dead types from database.ts/analytics.ts/helpers.ts
Phase 5: Strip shadcn/ui theme from tailwind config
Phase 6: Clean env vars, fix broken imports (LocalKeyGate, MapViewer)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

package.json

@@ -26,19 +26,12 @@
     "@ai-sdk/react": "^3.0.29",
     "@langchain/core": "^1.0.1",
     "@langchain/textsplitters": "^1.0.1",
-    "@radix-ui/react-checkbox": "^1.1.1",
-    "@radix-ui/react-dropdown-menu": "^2.1.1",
-    "@radix-ui/react-label": "^2.1.0",
-    "@radix-ui/react-slot": "^1.1.0",
     "@xyflow/react": "^12.10.0",
     "ai": "^6.0.27",
     "better-sqlite3": "^12.2.0",
     "cheerio": "^1.1.2",
-    "class-variance-authority": "^0.7.0",
-    "clsx": "^2.1.1",
     "lucide-react": "^0.468.0",
     "next": "15.1.3",
-    "next-themes": "^0.4.3",
     "openai": "^4.103.0",
     "pdf-parse": "^1.1.1",
     "pdfjs-dist": "^5.4.296",
@@ -46,12 +39,8 @@
     "react-dom": "^19.0.1",
     "react-markdown": "^10.1.0",
     "remark-gfm": "^4.0.1",
-    "tailwind-merge": "^2.5.2",
-    "uuid": "^11.1.0",
-    "youtube-captions-scraper": "^2.0.3",
     "youtube-transcript": "^1.2.1",
     "youtube-transcript-plus": "^1.1.1",
-    "ytdl-core": "^4.11.5",
     "zod": "^3.25.76"
   },
   "devDependencies": {
@@ -59,7 +48,6 @@
     "@types/node": "22.10.2",
     "@types/react": "^19.0.2",
     "@types/react-dom": "19.0.2",
-    "@types/uuid": "^10.0.0",
     "autoprefixer": "^10.4.20",
     "esbuild": "^0.23.1",
     "eslint": "^8.57.0",
@@ -67,7 +55,6 @@
     "postcss": "^8.4.49",
     "prettier": "^3.3.3",
     "tailwindcss": "^3.4.17",
-    "tailwindcss-animate": "^1.0.7",
     "tsx": "^4.19.4",
     "typescript": "^5.7.2",
     "vitest": "^3.2.4"