fix(web): apply category spec templates to /compare, leaderboard, spec export and API v1 #1166

Follow-up to #1142 / PR #1163 (P2 from its review).

#1163 adds getCategorySpecTemplate / applyCategorySpecTemplate in @repo/shared-data/rules and applies them to the product page, catalogue cards and home cards. These surfaces still read the raw stored fields, so an earbud can still show RAM, storage or a screen size there until each master is re-enriched or cleaned:

• /compare (apps/web/src/components/compare/CompareWorkspace.tsx): RAM, 5G (valHas5g) and memory rows.
• The spec export toolbar (apps/web/src/components/leaderboard/ProductSpecsExportToolbar.tsx) and leaderboard rows.
• buildKeySpecLine (apps/web/src/lib/product-competitors.ts) for products outside the detail page.
• REST API v1 GET /api/v1/rate/products[/slug]: decide whether the API returns stored data as is (documented) or the category-scoped view.

Also: a watch's free-text cellular.technology (for example "LTE / 5G") still renders as stored.

Acceptance

• No earbud value for screen, refresh rate, ppi, RAM, ROM or camera on /compare, the leaderboard or the export.
• No "5G" for a smartwatch on those surfaces.
• Tests per surface.