feat: add Turkish Airlines app (MCP with OAuth)

[notabd7-deepshard]

Turkish Airlines App

Adds the Turkish Airlines app to the Truffle app store. This app connects to the Turkish Airlines MCP server for:

• Flight search — by route, date, passengers
• Flight status — real-time by flight number or route
• Booking management — view details, baggage allowance, booking links
• Miles&Smiles — profile, expiring miles, flight bookings
• City guides and promotions

Files added

• truffile.yaml — app config and OAuth steps
• auth.py — OAuth token handling (extends RemoteMcpOAuth)
• config.py — constants and token helpers
• remote_mcp_compat.py — remote MCP module loader
• turkish_client.py — MCP client with session reset logic
• turkish_foreground.py — foreground app entrypoint with proxy server
• tools.py — static tool definitions
• icon.svg — airplane icon

OAuth flow

Uses dynamic client registration with the Turkish Airlines MCP server. User authenticates via the standard OAuth flow.

[notabd7-deepshard]

This PR was made with Abdullah's Truffle! 🍄