Extend reject + merge protection to vendor marketplaces

[whatrwewaitingf0r]

Problem

jaine-sync plugins reject <name>@<vendor-mp> silently fails for all vendor marketplaces:

reject@jaine-plugins:     ✓ works
reject@browserbase:       ✗ BROKEN (repo_path=None)
reject@claude-code-lsps:  ✗ BROKEN (repo_path=None)
reject@signoz-skills:     ✗ BROKEN (repo_path=None)

6 plugins already rejected via manual workaround instead of the command:

• browserbase: functions, browserbase-cli
• claude-code-lsps: ada-language-server, bsl-lsp, omnisharp, powershell-editor-services

Additionally, ensure_merge_protection short-circuits for browserbase (single-plugin repo) → marketplace.json merge=ours never written → upstream changes will silently override curation.

Root cause

get_repo_path_for_marketplace(mp) looks up manifest.marketplaces only. Vendor marketplaces use Repo.linked_marketplace field — different convention, different lookup.

ensure_merge_protection guard requires plugins/ or external_plugins/ dir. Single-plugin repos (source: "./") have neither.

Context

Original issue: #152 (closed, superseded). Primary pain points from #152 already solved:

• CalVer display → v3.45.2 (PR #160)
• Auto-bump SHA → v3.46.0 (PR #161)

This issue covers the REMAINING architectural gaps only.

Design

Spec: docs/superpowers/specs/2026-04-22-marketplace-curation-unification-design.md (v2)

3 phases, 1 PR, ~40 min:

Phase 1 — Schema + lookup

• Add linked_marketplace: jaine-plugins to claude-plugins-official in manifest.yaml
• Update get_repo_path_for_marketplace: try repos[*].linked_marketplace first, fallback to manifest.marketplaces

Phase 2 — Verify reject e2e

• Tests that reject@browserbase edits marketplace.json, commits, pushes, refreshes CC cache
• No code changes beyond Phase 1

Phase 3 — Merge protection guard

• Extend guard: trigger if .claude-plugin/marketplace.json exists at repo root (not only plugins/ dir)
• browserbase gets marketplace.json merge=ours on next sync

Acceptance criteria

• get_repo_path_for_marketplace('browserbase') → returns vendor repo path
• reject <name>@browserbase works end-to-end
• ensure_merge_protection writes marketplace.json merge=ours for browserbase
• All existing tests pass

Deferred (from original #152)

• CLI rename vendor→repo (cosmetic, functional as-is)
• Orphan detection for vendor marketplaces (no cases yet)
• Upstream alerts for vendor marketplaces (no upstream changes since fork)
• Lifecycle for primary (semantic mismatch — dropped in brainstorm)

[MukundaKatta]

The linked_marketplace lookup with fallback is the right shape. One edge case worth covering in Phase 1 tests: a name collision where both repos[*].linked_marketplace and manifest.marketplaces declare the same key but resolve to different paths. The lookup order ("vendor first, fallback to manifest") should be explicit in the function so future refactors don't silently flip it. Otherwise this looks ready to ship.