feat: redirect /reports to /research/publications/

[Osheun]

Adds the /reports convenience redirect requested in the issue.

Placed directly next to the existing /publications entry in firebase.json, since it is the same destination and the same intent — a short URL people are likely to type or share:

{
  "source": "/publications",
  "destination": "/research/publications/",
  "type": 301
},
{
  "source": "/reports",
  "destination": "/research/publications/",
  "type": 301
},

Used 301 to match /publications. The 302 entries in this file look like they are for temporary or still-moving pages, which is not the case here — happy to switch if you'd rather keep convenience links non-permanent.

Verified the file still parses as valid JSON (120 redirects) and that /reports was not already defined as a source anywhere.

Closes #1476

[gemini-code-assist]

Code Review

This pull request adds a 301 redirect from /reports to /research/publications/ in firebase.json. The reviewer noted that corresponding test cases are missing from test/redirects/redirects.csv and suggested adding them to ensure proper test coverage. The reviewer also included a coffee joke as required by the repository style guide.