fix: bundled extensions should not have download URLs

[mnriem]

Fixes #2151

Problem

Extensions from the default catalog (catalog.json) could not be installed because download_url pointed to GitHub release artifacts that don't exist. The git and selftest extensions are bundled with spec-kit and should never be downloaded from a URL.

When the bundled extension lookup failed (e.g., incomplete install), the code fell through to the catalog download path and hit a 404.

Changes

• extensions/catalog.json — Removed selftest (not a published extension). Replaced download_url with "bundled": true on the git entry.
• src/specify_cli/__init__.py — The extension add flow now checks for "bundled": true before attempting download. When a bundled extension can't be found locally, it shows a clear error with reinstall instructions.
• src/specify_cli/extensions.py — download_extension() checks for "bundled": true and raises a specific error instead of the generic "has no download URL".
• tests/test_extensions.py — Added 3 regression tests:
  • CLI gives actionable error when bundled extension is missing locally
  • download_extension() rejects bundled extensions with a clear message
  • Non-bundled extensions without a URL still get the original error

Testing

All 1232 tests pass.

[Copilot]

Pull request overview

Fixes installation failures for bundled core extensions by removing invalid download URLs from the default catalog and making the CLI/catalog logic explicitly treat bundled extensions as local-only.

Changes:

• Update default extension catalog to mark git as bundled and remove selftest from the catalog.
• Update extension add to detect bundled catalog entries and emit a reinstall-focused error when the bundled files aren’t present locally.
• Update ExtensionCatalog.download_extension() to emit a clearer bundled-specific error (and add regression tests around bundled/no-URL cases).

Show a summary per file

File	Description
extensions/catalog.json	Marks git as bundled (no URL) and removes selftest entry from default catalog.
src/specify_cli/__init__.py	Adds bundled-aware behavior in extension add with actionable error output when local bundled assets are missing.
src/specify_cli/extensions.py	Adds a bundled-specific error path in download_extension() when download_url is absent.
tests/test_extensions.py	Adds regression tests for bundled-missing CLI error and download_extension() error messaging.

Copilot's findings

Tip

Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

• Files reviewed: 4/4 changed files
• Comments generated: 2

[Copilot]

Pull request overview

This PR fixes installation failures for bundled extensions in the default extension catalog by preventing the CLI/catalog download path from being used when an extension is intended to be shipped inside the Spec Kit package.

Changes:

• Marked the git catalog entry as bundled (and removed the unpublished selftest entry) to avoid invalid release-artifact download URLs.
• Updated specify extension add to detect bundled extensions from catalog metadata and emit an actionable reinstall error if the bundled payload is missing locally.
• Updated ExtensionCatalog.download_extension() to explicitly reject bundled-without-URL entries with a specific error, and added regression tests for these behaviors.

Show a summary per file

File	Description
extensions/catalog.json	Removes selftest and marks git as "bundled": true to prevent broken download attempts.
src/specify_cli/__init__.py	Adds bundled-aware handling in extension add with a clearer error when the bundled payload can’t be found locally.
src/specify_cli/extensions.py	Adds a bundled-specific guard in download_extension() and centralizes reinstall guidance via REINSTALL_COMMAND.
tests/test_extensions.py	Adds regression tests covering bundled-missing behavior and error messaging in both CLI and catalog download code paths.

Copilot's findings

Tip

Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

• Files reviewed: 4/4 changed files
• Comments generated: 0 new