fix: recover dashboard terminal transports when websocket sidecars fail

[harsh-batheja]

Summary

• add an in-process terminal transport supervisor that probes the 14800/14801 websocket services, restarts them when they fail, and exposes degraded transport state through a new terminal health API plus the existing session APIs
• surface terminal transport degradation in the dashboard and session terminal UI so active sessions remain visible while websocket services recover instead of silently losing the interface
• align ao start with the supervised Next.js launch path and add regression coverage for restart recovery, port-conflict degradation, API health exposure, and the dashboard banner

Verification

• corepack pnpm --filter @composio/ao-web test -- src/lib/__tests__/terminal-transport.test.ts src/__tests__/api-routes.test.ts src/components/__tests__/Dashboard.terminalHealth.test.tsx src/components/__tests__/DirectTerminal.test.ts
• corepack pnpm --filter @composio/ao-cli test -- __tests__/commands/start.test.ts
• corepack pnpm --filter @composio/ao-web typecheck
• corepack pnpm -r build

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

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