Google Flights airline logo assets are missing

[hqhq1025]

Problem

Google Flights flights/search pages reference airline logos via Flight.airline_logo, but the Google Flights asset bundle does not include the referenced airline logo files. The templates therefore hide the broken image on error, leaving blank airline logo slots.

seed_data.py currently writes paths like:

/static/images/airlines/<airline>.svg

but the asset bundle has no airline logo files.

Expected

All seeded airline logos should exist in the HF-managed Google Flights asset tarball and render on flights/search/detail pages.

Proposed Fix

• Add Google Flights airline logo assets for all 23 seeded airlines.
• Use Google Flights gstatic airline logos (/flights/airline_logos/70px/{code}.png) as the source.
• Update seed data to point at .png assets.
• Upload updated google_flights.tar.gz to the HF dataset.

[hqhq1025]

HF asset PR is open at https://huggingface.co/datasets/ChilleD/WebHarbor/discussions/11. It adds all 23 PNG airline logos to google_flights.tar.gz; the paired GitHub PR is #23.