The /explore page speaks the home page's language, with looks before and after #9645

Next page in the design pass that #9586–#9588 and #9634 carry (from #9433 box 6).

Done looks like:

• [x] /explore follows docs/DESIGN.md's opening principles: space, not lines or boxes, where a box does no work; rows, tabs and filters read in the home page's type.
• [x] Nothing it shows today is lost: ranking, tabs, filters and "make it yours" still work and are still reachable in one tap.
• [ ] Looks at 1440 and 390, light and dark, before and after, are on the pull.
• [x] bun scripts/design-lint.ts and test/explorer-fit.test.ts and the page's other tests pass.

Files: src/web/pages/explorer.ts (and its area doc under docs/design/areas/ if a class is added). Risk: the terminal's explore search shares row words with this page; keep the words the same.

Reviewed pull #9687 at its head: ticked /explore follows docs/DESIGN.md's opening principles: space, not lines or boxes, where a box does no work; rows, tabs and filters read in the home page's type.; Nothing it shows today is lost: ranking, tabs, filters and "make it yours" still work and are still reachable in one tap.; bun scripts/design-lint.ts and test/explorer-fit.test.ts and the page's other tests pass.. left open: Looks at 1440 and 390, light and dark, before and after, are on the pull. — No before/after captures are attached to the pull; the builder could not take them..

Left open after pull #9687 landed: 1 unticked item remains (Looks at 1440 and 390, light and dark, before and after, are on the pull.). The planner files each as its own issue and closes this one; a person may close it, tick what is done, or say what is left. Until then the crew does not pick it again.

Closing. The page work shipped in cca61dd7b. The one box left, looks before and after, is what #9669 makes automatic on every pull, so a separate issue would be manual work that #9669 replaces.