[community] Update SpecAssay to v0.4.13 (extension, preset, bundle)

[rdryfoos]

Description

Version-bump for the three SpecAssay community catalog entries, from v0.4.12 to v0.4.13: specassay-check (extension), specassay (preset), and specassay (bundle). Same fields the previous update PRs changed (#4254, #4256, #4257): version, download_url, updated_at, plus the extension's provides.commands (2 to 5; the extension has shipped five commands since dig, matrix, and portfolio landed). All three move together in one PR because the bundle pins its component versions; bumping one entry alone would make specify bundle install specassay fail resolution.

Release: https://github.com/rdryfoos/specassay/releases/tag/v0.4.13 (tag 105c4845f8ae88f1af361d56c0de458089b50fad, built and published by the repo's Release workflow). Asset digests, as reported by GitHub's release API and re-verified by download:

• specassay-check-0.4.13.zip: sha256:d7ac14c271b99aff0b649def9c3444b6e03090649df43ea2b9c3949ded91ed9f
• specassay-preset-0.4.13.zip: sha256:ed4298d72b80f083400c0ac7bcbf9a3eb5d5950eb50abd542e8fc4b5b77d8a58
• specassay-0.4.13.zip: sha256:8529e8b7542a712542321856368b4f3d7f2f820f98350f7c7f7115670005f18d

What v0.4.13 changes for a first-time installer, briefly: the Gate detects python3 or python (Windows Git Bash works), reports its config state on startup, and explains what to do when the registry is empty instead of printing a bare OK. Full notes: https://github.com/rdryfoos/specassay/blob/main/CHANGELOG.md. The submission-form issues with the complete test evidence for this version will follow per the publishing guides; this PR is only the catalog pointer, so people installing from the community catalog stop landing on the version whose cold-install dead end v0.4.13 fixes.

Testing

• Clean specify init project, catalogs added install-allowed, specify bundle install specassay at 0.4.13: 2 components installed, specify extension list reports v0.4.13 with Commands: 5 | Hooks: 1.
• Upgrade from a real v0.4.12 catalog install: specify bundle update specassay moves both components to v0.4.13 with the user's edited config preserved.
• Full transcript with digests: https://github.com/rdryfoos/specassay/blob/main/docs/submission/test-evidence.md
• Tested locally with uv run specify --help (not applicable: JSON catalog data only)
• Ran existing tests with uv sync && uv run pytest (not applicable: JSON catalog data only)

AI Disclosure

• I did not use AI assistance for this contribution
• I did use AI assistance (describe below)

Claude Code (Anthropic) prepared the JSON edits and this PR text under the maintainer's direction; the release, digests, and install tests were run and verified by the same session against the real CLI.