feat: legacy router migration 4

[Alessandro100]

Summary:

closes #26

Removes the legacy router and all traces of the old React App

Expected behavior:

App should run as usual

Testing tips:

Provide tips, procedures and sample files on how to test the feature.
Testers are invited to follow the tips AND to try anything they deem relevant outside the bounds of the testing tips.

Please make sure these boxes are checked before submitting your pull request - thanks!

• Run the unit tests with yarn test to make sure you didn't break anything
• Add or update any needed documentation to the repo
• Format the title like "feat: [new feature short description]". Title must follow the Conventional Commit Specification(https://www.conventionalcommits.org/en/v1.0.0/).
• Linked all relevant issues
• Include screenshot(s) showing how this pull request works and fixes the issue(s)

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Project	Deployment	Actions	Updated (UTC)
mobilitydatabase-web	Ready	Preview, Comment	Apr 30, 2026 5:30pm

[github-actions]

*Lighthouse ran on https://mobilitydatabase-hb5qydjvn-mobility-data.vercel.app/ * (Desktop)
⚡️ HTML Report Lighthouse report for the changes in this PR:

Performance	Accessibility	Best Practices	SEO
🟢 98	🟢 94	🟢 96	🟢 100

*Lighthouse ran on https://mobilitydatabase-hb5qydjvn-mobility-data.vercel.app/feeds * (Desktop)
⚡️ HTML Report Lighthouse report for the changes in this PR:

Performance	Accessibility	Best Practices	SEO
🟠 82	🟠 87	🟢 96	🟢 100

*Lighthouse ran on https://mobilitydatabase-hb5qydjvn-mobility-data.vercel.app/feeds/gtfs/mdb-2126 * (Desktop)
⚡️ HTML Report Lighthouse report for the changes in this PR:

Performance	Accessibility	Best Practices	SEO
🟠 55	🟢 94	🟢 96	🟢 100

*Lighthouse ran on https://mobilitydatabase-hb5qydjvn-mobility-data.vercel.app/feeds/gtfs_rt/mdb-2585 * (Desktop)
⚡️ HTML Report Lighthouse report for the changes in this PR:

Performance	Accessibility	Best Practices	SEO
🟢 99	🟠 84	🟢 96	🟢 100

*Lighthouse ran on https://mobilitydatabase-hb5qydjvn-mobility-data.vercel.app/feeds/gbfs/gbfs-flamingo_porirua * (Desktop)
⚡️ HTML Report Lighthouse report for the changes in this PR:

Performance	Accessibility	Best Practices	SEO
🟢 95	🟢 94	🟢 96	🟢 100

[davidgamez]

Do we have an issue for following up on this?

[Alessandro100]

yes we do #116

[davidgamez]

LGTM!