feat(repo): centralized repositories.json catalog, multi-distro expansion & worker live sync

[brasga-a]

Summary

This PR establishes a centralized repository catalog repositories.json in the Git repository root as the single source of truth for official repositories, expands distribution coverage to 22 official repositories, and integrates live synchronization into the Cloudflare Worker.

1. Centralized repositories.json Catalog

• Defined top-level repositories.json adhering to schema_version: "1.0".
• Expanded from 10 to 22 official repositories across:
  • Arch Linux: arch-core, arch-extra, arch-multilib (ALPM)
  • Ubuntu: ubuntu-noble (24.04), ubuntu-resolute (26.04), ubuntu-jammy (22.04), ubuntu-focal (20.04) (DEB)
  • Debian: debian-bookworm (12), debian-trixie (13), debian-sid (unstable), debian-bullseye (11) (DEB)
  • Fedora: fedora-41, fedora-42, fedora-40 (RPM)
  • openSUSE: opensuse-tumbleweed, opensuse-leap-15-6 (RPM)
  • Alpine Linux: alpine-v3.20, alpine-edge (APK)
  • AlmaLinux & Rocky Linux: almalinux-9-baseos, almalinux-9-appstream, rocky-9-baseos, rocky-9-appstream (RPM)

2. Zero Duplication in pkg-core

• crates/pkg-core/src/repository/config.rs now embeds repositories.json at compile-time via include_str!("../../../../repositories.json").
• Added heuristic fallbacks for openSUSE, Alpine, AlmaLinux, and Rocky Linux.

3. Cloudflare Worker Dynamic Sync

• infra/cloudflare/src/index.js fetches repositories.json directly from GitHub (raw.githubusercontent.com) with 5-minute CDN edge caching (cacheTtl: 300).
• Any repository added or updated in git is instantly reflected on https://pkg.atlantic.sh/repositories without requiring manual worker redeployments.
• Static fallback preserved for resilience against network failures.

4. Tests & Verification

• Full test suite passing (cargo test --workspace).
• cargo fmt --all --check and cargo clippy 100% clean.