bug: remove Claude and Codex plugin state during global uninstall

[kaitranntt]

Description

Global Engineer uninstall removes the Claude plugin but leaves the Codex plugin and marketplace registration behind.

Root Cause

The normal uninstall path calls uninstallEnginePlugin() only; Codex cleanup is wired only into explicit legacy-mode initialization.

Acceptance Criteria

• Global/all Engineer uninstall removes both provider plugins and their owned marketplace state.
• Project-only and non-Engineer uninstall do not remove global plugin state.
• Cleanup is idempotent and preserves unrelated marketplaces/plugins.
• Verification failures prevent a false success result.
• Tests cover first and repeated uninstall.

Affected Files

• src/commands/uninstall/uninstall-command.ts
• src/domains/installation/plugin/*uninstall*
• uninstall tests

[kaitranntt]

Implemented in #923 and released to the dev channel in v4.5.2-dev.6.

[kaitranntt]

Fixed by #924 and released on the dev channel in v4.5.2-dev.7. Marketplace-only Claude state is now removed and verified without touching unrelated plugin ownership.