Airline integration work: AirlineLoadService updates, docs, JSX scripts

- AirlineLoadService: pass airport DB for timezone-aware date strings,
  add browser-shaped headers for United, expand JetBlue/Alaska/Emirates
  signatures to take origin, log/parse fixes for Korean Air.
- FlightsApp: build AirlineLoadService with the airport DB and inject it.
- JSX: continued WebView-based fetcher work plus updated JSX_NOTES.
- Docs: add AIRLINE_INTEGRATION_GUIDE.md, drop the old AIRLINE_API_SPEC.md,
  add api_docs/ (StaffTraveler reverse-engineering captures + findings).
- Scripts: jsx_cdp_probe, jsx_live_monitor, jsx_swift_smoke for JSX
  protocol exploration.
- .gitignore: exclude airlines/ (local-only APK/IPA reverse-engineering).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

api_docs/stafftraveler_captures/createLoadsRequests_AA2178_response_headers.txt

@@ -0,0 +1,12 @@
+HTTP/2 200 
+access-control-allow-credentials: true
+cache-control: no-store
+content-type: application/json
+vary: Origin
+x-cloud-trace-context: 7f1fda60d8d56f8106053d5e7df58556
+date: Wed, 22 Apr 2026 18:40:54 GMT
+server: Google Frontend
+content-length: 1070
+via: 1.1 google
+alt-svc: h3=":443"; ma=2592000,h3-29=":443"; ma=2592000
+