Add extended promotional component filter

[Serve63]

/claim #92

Summary

• add is_extended_promotional query support for component search and component lists
• derive the field from preferred = 1 and basic = 0 in API responses
• pass the filter through the Cloudflare proxy and expose it in the HTML filter UI
• update the setup script to use current 7-Zip 26.01 tarballs so CI can fetch its extraction binary
• let the Bun test workflow reuse existing DB caches and allow enough time for a fresh DB setup when the cache misses

Validation

• npm test in cf-proxy (126 tests passed)
• npx tsc --noEmit --pretty false in cf-proxy
• npx --yes -p typescript@5.7.3 tsc --noEmit --pretty false at repo root
• npx --yes @biomejs/biome@1.9.4 format ... on changed files
• git diff --check
• verified 7-Zip 26.01 Linux x64, Linux arm64, and macOS tarball URLs return HTTP 200

CI note

The first PR test run reached the existing 20-minute timeout during database setup before tests started. The workflow change keeps bun test intact; it only restores compatible DB caches by prefix and gives uncached setup enough time to complete.

[Serve63]

Added a short UI demo for the bounty guideline:

• Demo video: https://github.com/Serve63/jlcsearch/releases/download/pr-343-extended-promotional-demo/extended-promotional-filter-demo.webm
• Screenshot: https://github.com/Serve63/jlcsearch/releases/download/pr-343-extended-promotional-demo/extended-promotional-filter.png

The demo shows the Components page with the Extended Promotional checkbox selected, the filtered result, and the Extended Promotional response/table column visible.