The explorer's filters live in the URL: a filtered view reloads, shares and goes back to the same results #11431

One sentence: a filter set on the explorer is a link, not a state.

Done looks like:

• [ ] Every explorer filter (kind, sort, freshness, text) is read from and written to the query string; an unknown or malformed value is ignored at the boundary, never echoed unescaped.
• [ ] Reload, copy-link and browser Back return to the same results, server-rendered, with no extra JavaScript.
• [ ] A test fails without it: a request with filters in the URL renders the filtered rows and marks the active filters.
• [ ] Reachable: linked from the home feed's explorer door in two taps; docs/ line says the URL shape.

Files expected: src/web/pages/browse.ts, src/actions/explore.ts, test/ for the explorer page. Risks: clashes with #11323/#11376 (same page): keep to parsing and writing the query, leave counts and the More link to them. Suggested brief: scout (explorer work).

Done on main already, waiting for you to close it: 4b1730336312bb24148c169fbe8ab04a9cf506db b93ecb38a527812097be149fc6c7c01d79ecf5a3

Closed: already done on main in 4b17303, b93ecb3. Closed by the crew's live triage; reopen it to undo, and it stays open.