fix: comprehensive QA audit — light mode, accessibility, error handling, code quality

- Fix light mode: theme-aware graph node labels, remove prose-invert for
  theme-safe markdown, add brand/semantic color overrides for light backgrounds
- Add 404 catch-all route redirecting unknown paths to /chat
- FalkorDB: add .catch() to connectPromise, add ensureConnected() to all
  store methods (createLiteral, relateNode, relateLiteral, deleteCollection)
- Accessibility: dialog role/aria-modal, toast aria-live, dismiss/zoom/search
  button aria-labels, close panel aria-label
- Lazy-load ForceGraph2D (splits 189KB into separate chunk, main bundle -26%)
- Cap conversation localStorage at 200 messages to prevent quota overflow
- Fix pnpm test: add --passWithNoTests to cli/mcp packages
- Add upload error notification instead of silent catch
- Remove unused class-variance-authority dep and dead tabs.tsx component
- Add @types/node to flow package devDependencies
- Remove stale FIXME comment in messages.ts

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ts/packages/cli/package.json

@@ -9,7 +9,7 @@
     "build": "tsc",
     "dev": "tsc --watch",
     "clean": "rm -rf dist",
-    "test": "vitest run"
+    "test": "vitest run --passWithNoTests"
   },
   "dependencies": {
     "@trustgraph/base": "workspace:*",