feat: add Koa2 BFF server, CLI management, sessions CLI integration, and logs page

- Add Koa2 BFF layer for API proxy, file upload, session management
- Auto-check and enable api_server in ~/.hermes/config.yaml on startup
- Integrate sessions with Hermes CLI (list, get, delete)
- Add Logs page with level filtering, log file selection, and search
- Add CLI commands: start/stop/restart/status for daemon management
- Unify package.json for frontend and server dependencies
- Default port changed to 8648

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/api/logs.ts

@@ -0,0 +1,36 @@
+import { request } from './client'
+
+export interface LogFileInfo {
+  name: string
+  size: string
+  modified: string
+}
+
+export interface LogEntry {
+  timestamp: string
+  level: string
+  logger: string
+  message: string
+  raw: string
+}
+
+export async function fetchLogFiles(): Promise<LogFileInfo[]> {
+  const res = await request<{ files: LogFileInfo[] }>('/api/logs')
+  return res.files
+}
+
+export async function fetchLogs(name: string, params?: {
+  lines?: number
+  level?: string
+  session?: string
+  since?: string
+}): Promise<LogEntry[]> {
+  const query = new URLSearchParams()
+  if (params?.lines) query.set('lines', String(params.lines))
+  if (params?.level) query.set('level', params.level)
+  if (params?.session) query.set('session', params.session)
+  if (params?.since) query.set('since', params.since)
+  const qs = query.toString()
+  const res = await request<{ entries: (LogEntry | null)[] }>(`/api/logs/${name}${qs ? `?${qs}` : ''}`)
+  return res.entries.filter((e): e is LogEntry => e !== null)
+}