chore: release v5.2.1

[avifenesh]

Summary

• bump agentsys version to 5.2.1 across stamped version files and add changelog release entry
• harden plugin source parsing in installer for both legacy string and structured object source fields
• improve GitHub tarball fetch with ref fallback order (vX.Y.Z, X.Y.Z, main, master) and fail-fast behavior when any plugin fetch fails
• fix install ordering so local install reset no longer deletes fetched plugin cache before OpenCode/Codex/Cursor installation
• add/keep regression tests for source normalization and GitHub source parsing

Test Plan

• npm test
• npm test -- cli-args.test.js cli-subcommands.test.js --runInBand
• npx agentsys-dev validate consistency
• npx agentsys-dev preflight --release
• npm pack --dry-run
• npm pack && npm install -g ./agentsys-5.2.1.tgz && echo "1 2 3" | agentsys

[Copilot]

Pull request overview

This is a patch release (v5.2.1) that hardens the plugin installation system. It fixes the plugin.source.startsWith is not a function crash by introducing resolvePluginSource() to normalize both legacy string and structured object source formats. It also improves GitHub tarball fetching with a multi-ref fallback strategy, adds fail-fast behavior when any plugin fetch fails, and fixes the install ordering so the local install directory reset no longer wipes the fetched plugin cache before OpenCode/Codex/Cursor installation.

Changes:

• Version bumped to 5.2.1 across all version stamp files and a CHANGELOG entry added
• resolvePluginSource() added to handle both legacy string and structured {source, url/path} marketplace source formats; parseGitHubSource() extracted into its own testable function with improved ref fallback order
• Install ordering in main() fixed so fetchExternalPlugins runs after the local install directory is set up rather than before

Reviewed changes

Copilot reviewed 6 out of 8 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
bin/cli.js	Core logic: new resolvePluginSource, extracted parseGitHubSource, improved fetch retry loop, install ordering fix, fail-fast behavior, and new exports
__tests__/cli-subcommands.test.js	Regression tests for resolvePluginSource and parseGitHubSource
CHANGELOG.md	New 5.2.1 release entry documenting the three fixes
package.json	Version bump to 5.2.1
package-lock.json	Version bump to 5.2.1
site/content.json	Version bump to 5.2.1
.claude-plugin/plugin.json	Version bump to 5.2.1
.claude-plugin/marketplace.json	Version bump to 5.2.1

---

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