refactor: trust shipped plugin sources

[HANCORE-linux]

Summary

• retarget capability assertions, models, and smokes to the shipped hancore.shibumi.* sources
• make Bluetooth, AI, Workspace, GPU, and helper ownership explicitly plugin-canonical
• add a compact production-boundary gate with source, package-workflow, and release-archive coverage
• retire the unguarded historical root implementation and superseded root smokes while preserving declared bar-host and shared/** vendoring
• update architecture and evidence contracts to describe the shipped process-wide owners

Validation

• complete contract regression against installed-source parity (b99fd91)
• complete contract regression against forward compatibility (d6b21f8)
• package tests: 12 passed
• suite install/update/rollback/recovery tests: 99 passed
• manager tests: 29 passed
• health tests: 31 passed
• production-boundary tests: 8 passed
• shared and bar-host vendoring checks
• AUR scaffold, documentation, syntax, and diff checks
• independent review: no actionable findings

No shipped plugin presentation changed in the final root-retirement slice.