Align backend startup port to environment configuration

Add startup port debug and OpenAPI path logging

Use start_backend.py in Docker CMD and improve nested route debugging

Legacy text routes now fallback to guest access when auth token is missing or invalid

Allow legacy text endpoints to use guest auth when no Authorization header is present

Debug: print registered FastAPI routes at startup

Include legacy_router so /analyze/text works

Restore legacy /analyze/text endpoints (compatibility)

Fix encoding: convert main.py to UTF-8

Add legacy compatibility endpoints for /analyze/text

Apply Dockerfile change: skip warmup & force CPU torchcodec

Add async SMTP dependency

Remove env example with personal data

Deploy backend updates

Production Deploy: Improved robustness and logging