App Store source support added; documentation updated

Minor Changes

• 8935518: Add App Store source support to the admin CLI.
  • New releases admin source create-appstore <url-or-id> verb — accepts an apps.apple.com URL, a bare numeric track ID, or an appstore:<trackId> coordinate, with --platform ios|macos, --org, --product, --storefront, --json, and --dry-run. It calls POST /v1/sources/appstore, which resolves the listing, mints the first release, and backfills the product's app-icon avatar.
  • releases admin source create now recognizes appstore as a valid type and rejects --type appstore / pasted apps.apple.com URLs with a pointer to create-appstore (source types are now sourced from @buildinternet/releases-core instead of a hard-coded list).
  • releases admin product list and releases get <product> surface the product avatarUrl (the app icon).

Patch Changes

• 7a28fc2: Document the source create-appstore verb in the releases-cli admin skill reference: a dedicated "Create App Store source" section (identifier forms, --platform/--storefront, idempotency, the pre-create-product workflow) plus a note on the create command that App Store apps use it.
• ed73777: Document Firecrawl monitoring as a fetch backend in the changelog skills: add it as step 5 of the parsing-changelogs pipeline overview, and note in managing-sources / finding-changelogs that for sources behind a Cloudflare Managed Challenge (persistent no_change / 0 releases that --render can't fix), Firecrawl is enabled per-source via the admin API (POST /v1/sources/:slug/firecrawl/sync), not a CLI verb or --metadata-set.