feat(web-console): cherry-pick React web console GUI from gary-the-ai fork

Cherry-pick the Hermes Web Console from gary-the-ai/hermes-web-console-gui.
React + TypeScript frontend with Vite, Python aiohttp backend API.

Components:
- web_console/ — React frontend (chat, sessions, memory, settings, skills,
  gateway config, cron, workspace, tools, browser, insights pages)
- gateway/web_console/ — Python backend API (23 endpoints, SSE event bus,
  11 service modules)
- gateway/platforms/api_server_ui.py — embedded browser UI for API server
- gateway/platforms/api_server.py — route registration refactored into
  _register_routes(), web console mounted via maybe_register_web_console()
- run-gui.sh / setup-gui.sh — one-command launch and setup scripts
- tests/gateway/test_api_server_gui_mount.py — 4 integration tests (passing)
- tests/web_console/ — 13 backend test files (51 passing)
- docs/plans/ — implementation plan, API schema, frontend architecture

Fix: added missing ModelContextError class and CRON_MIN_CONTEXT_TOKENS to
cron/scheduler.py (pre-existing import bug).

Closes #325

web_console/package.json

@@ -0,0 +1,37 @@
+{
+  "name": "hermes-web-console",
+  "private": true,
+  "version": "0.1.0",
+  "type": "module",
+  "scripts": {
+    "dev": "vite",
+    "build": "vite build",
+    "preview": "vite preview",
+    "test": "vitest run"
+  },
+  "dependencies": {
+    "@types/react-syntax-highlighter": "^15.5.13",
+    "@xterm/addon-fit": "^0.11.0",
+    "@xterm/xterm": "^6.0.0",
+    "react": "^19.0.0",
+    "react-dom": "^19.0.0",
+    "react-markdown": "^10.1.0",
+    "react-syntax-highlighter": "^16.1.1",
+    "recharts": "^3.8.1",
+    "rehype-highlight": "^7.0.2",
+    "rehype-katex": "^7.0.1",
+    "remark-gfm": "^4.0.1",
+    "remark-math": "^6.0.0"
+  },
+  "devDependencies": {
+    "@testing-library/jest-dom": "^6.6.3",
+    "@testing-library/react": "^16.3.0",
+    "@types/react": "^19.0.10",
+    "@types/react-dom": "^19.0.4",
+    "@vitejs/plugin-react": "^4.3.4",
+    "jsdom": "^26.0.0",
+    "typescript": "^5.6.3",
+    "vite": "^6.2.0",
+    "vitest": "^3.0.7"
+  }
+}