feat: merge people search into the recipe search bar on Explore

People search existed but was buried in its own tab with no entry
point from anywhere else — easy to conclude it "doesn't work" since
nobody would find it. Now one query on Explore hits both
/api/v1/search and /api/v1/users/search and renders People/Recipes
sections together; the standalone people tab and its now-dead
PeopleSearch component are gone.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "epicure",
-  "version": "0.12.1",
+  "version": "0.13.0",
   "private": true,
   "scripts": {
     "dev": "pnpm --filter web dev",