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

tests/web_console/test_logs_api.py

@@ -0,0 +1,64 @@
+"""Tests for the web console logs API."""
+
+from __future__ import annotations
+
+import pytest
+from aiohttp import web
+from aiohttp.test_utils import TestClient, TestServer
+
+from gateway.web_console.api.logs import LOG_SERVICE_APP_KEY
+from gateway.web_console.routes import register_web_console_routes
+
+
+class FakeLogService:
+    def get_logs(self, *, file_name=None, limit=200):
+        if file_name == "missing.log":
+            raise FileNotFoundError(file_name)
+        return {
+            "directory": "/tmp/hermes/logs",
+            "file": file_name or "gateway.log",
+            "available_files": ["gateway.log", "gateway.error.log"],
+            "line_count": min(2, limit),
+            "lines": ["line 1", "line 2"][:limit],
+        }
+
+
+class TestLogsApi:
+    @staticmethod
+    async def _make_client(service: FakeLogService) -> TestClient:
+        app = web.Application()
+        app[LOG_SERVICE_APP_KEY] = service
+        register_web_console_routes(app)
+        client = TestClient(TestServer(app))
+        await client.start_server()
+        return client
+
+    @pytest.mark.asyncio
+    async def test_get_logs_route(self):
+        client = await self._make_client(FakeLogService())
+        try:
+            resp = await client.get("/api/gui/logs?file=gateway.error.log&limit=1")
+            assert resp.status == 200
+            payload = await resp.json()
+            assert payload["ok"] is True
+            assert payload["logs"]["file"] == "gateway.error.log"
+            assert payload["logs"]["line_count"] == 1
+            assert payload["logs"]["lines"] == ["line 1"]
+        finally:
+            await client.close()
+
+    @pytest.mark.asyncio
+    async def test_get_logs_route_validation_and_not_found(self):
+        client = await self._make_client(FakeLogService())
+        try:
+            invalid_limit_resp = await client.get("/api/gui/logs?limit=abc")
+            assert invalid_limit_resp.status == 400
+            assert (await invalid_limit_resp.json())["error"]["code"] == "invalid_limit"
+
+            missing_resp = await client.get("/api/gui/logs?file=missing.log")
+            assert missing_resp.status == 404
+            missing_payload = await missing_resp.json()
+            assert missing_payload["error"]["code"] == "log_not_found"
+            assert missing_payload["error"]["file"] == "missing.log"
+        finally:
+            await client.close()