Add extended promotional boolean filter

[YunHeTracyLee]

/claim #92

Summary

• Derive is_extended_promotional from existing JLC flags as preferred = 1 and basic = 0.
• Expose the field in /components/list and /api/search responses, including full=true components-list responses.
• Support both is_extended_promotional=true and is_extended_promotional=false filtering in the origin routes and D1 proxy search/catalog paths.
• Add the Extended Promotional filter/column label to rendered component-list pages.
• Add focused helper coverage and D1 render coverage.

Non-overlap

Most existing #92 PRs cover the true-only checkbox/filter path. This PR keeps the same derived-field behavior but makes the query filter a full boolean API (true and false) while keeping the UI checkbox path intact.

Validation

• npx --yes bun test tests/lib/extended-promotional.test.ts
• npx --yes bun x biome check lib/util/extended-promotional.ts routes/components/list.tsx routes/api/search.tsx tests/lib/extended-promotional.test.ts cf-proxy/src/extended-promotional.ts cf-proxy/src/search.ts cf-proxy/src/components.ts cf-proxy/src/index.ts cf-proxy/src/render.ts cf-proxy/test/render.test.ts
• npx --yes bun x tsc --noEmit
• cd cf-proxy && npx --yes bun x tsc --noEmit && npx --yes bun test test/render.test.ts
• git diff --check

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