fix(status): match branch-qualified cache for GitHub plugins

[christso]

Summary

• workspace status reported ✗ not cached for any GitHub plugin whose source pins a branch (e.g. /blob/main/... or owner/repo@v1), even immediately after a successful skills add.
• Root cause: parsePluginSource discarded the branch field returned by parseGitHubUrl, so getPluginStatus called getPluginCachePath(owner, repo) without it and looked at ~/.allagents/plugins/marketplaces/<owner>-<repo>. But fetchPlugin (src/core/plugin.ts:102,160) and seedCacheFromClone (src/core/workspace.ts:381) write to <owner>-<repo>@<branch>, so the existence check always missed.
• Fix: add branch?: string to ParsedPluginSource, populate it in parsePluginSource, and pass it through to getPluginCachePath in getPluginStatus. No other call sites needed changes — they already pass branch directly.

Repro (before)

$ npx allagents skills add https://github.com/NousResearch/hermes-agent/blob/main/skills/research/llm-wiki
✓ Enabled skill: llm-wiki (llm-wiki)
$ npx allagents workspace status
Project Plugins (1):
  ✗ https://github.com/.../llm-wiki (not cached)

After the fix, the same command reports ✓ ... (cached).

Test plan

• bun test tests/unit/utils/plugin-path.test.ts tests/unit/core/status-both-scopes.test.ts — added one test for parsePluginSource returning branch from a /blob/ URL, one for owner/repo@ref shorthand, and one regression test asserting status reports available: true against a branch-qualified cache dir.
• bun test — full suite (1285 pass, 4 skip, 0 fail).
• bun run typecheck — clean.
• End-to-end: built CLI against an existing workspace with a /blob/main/... source — status flipped from ✗ not cached to ✓ cached.

🤖 Generated with Claude Code

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View logs

[christso]

E2E verification log

Fresh temp dir, same commands the user originally ran. Same cache state for both runs — only the CLI binary changes.

Setup

$ REPRO=$(mktemp -d -t ux-verify-XXXXXX)
$ cd "$REPRO"

$ npx -y allagents@1.11.9 workspace init . --client claude
✓ Workspace created at: /tmp/ux-verify-cBroAT

Syncing plugins...

$ npx -y allagents@1.11.9 skills add https://github.com/NousResearch/hermes-agent/blob/main/skills/research/llm-wiki
Installing skill 'llm-wiki' from https://github.com/NousResearch/hermes-agent/blob/main/skills/research/llm-wiki...
✓ Enabled skill: llm-wiki (llm-wiki)

.allagents/workspace.yaml:

repositories: []
plugins:
  - source: https://github.com/NousResearch/hermes-agent/blob/main/skills/research/llm-wiki
    skills:
      - llm-wiki
clients:
  - claude
version: 2

Cache on disk (note the @main suffix written by the fetcher):

$ ls -d ~/.allagents/plugins/marketplaces/NousResearch*
/home/entity/.allagents/plugins/marketplaces/NousResearch-hermes-agent@main

Before (allagents@1.11.9 from npm)

$ npx -y allagents@1.11.9 workspace status
Project Plugins (1):
  ✗ https://github.com/NousResearch/hermes-agent/blob/main/skills/research/llm-wiki (not cached)

User Plugins (0):
  No user plugins configured

Clients (1):
  claude

After (this PR's build)

$ node /path/to/dist/index.js workspace status
Project Plugins (1):
  ✓ https://github.com/NousResearch/hermes-agent/blob/main/skills/research/llm-wiki (cached)

User Plugins (0):
  No user plugins configured

Clients (1):
  claude

Only the ✗ ... (not cached) → ✓ ... (cached) line changes — everything else (header counts, indentation, client list) is byte-identical.