* Package BCQuality as an installable plugin (experiment)
Adds a marketplace + plugin manifest and a bridge review skill that drives the existing Entry protocol from a plugin host. No changes to knowledge or routing logic.
* Bridge skill: make enabled-layers configurable; note layer-pruning limit and manifest choice
Addresses PR #84 review (JesperSchulz): #2 layer policy has no hook in the plugin path -> expose BCQUALITY_ENABLED_LAYERS and document that it narrows discovery only, not a hard deny; #3 document the .claude-plugin manifest choice (verified on Copilot CLI).
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Co-authored-by: wenjiefan <wenjiefan@microsoft.com>
