feat(mcp): expose preview list and close

[juliusmarminge]

Part 9/16 of the shared-core and MCP stack. Based on #10558. Next: #10560.

Expose the existing PreviewManager list and explicit-tab close operations for the calling thread.

The existing preview capability and browser-access setting are required. Close uses the existing server/host lifecycle and does not claim renderer cleanup has finished. Broker race hardening is separate.

MCP-only rebuild of #8724, preserving attribution to Julius Marminge's original work. Original branches remain available for separate service follow-ups.

Validation: The composed stack passes 94 tests across 12 focused files, including shared core MCP and real MCP/V2 integration, attachment intake, project RPC/service contracts, and client model command selection. Server/contracts/shared/client-runtime typechecks and targeted format/lint/diff checks pass. New behavior coverage lives with the shared operation; no per-tool mock suite was added. Current-head CI is shown below.

Layer size: 7 files, +102/-1. No domain-service production implementation or documentation files change in this MCP layer.

Prepared with Codex in the OpenAI agent runtime.

[cursor]

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[macroscopeapp]

Approvability

Verdict: Not approved

Macroscope's review found this PR not approvable — This PR adds two production MCP capabilities for preview-tab discovery and closure, including a destructive close operation and a broader read-only Claude tool surface. The implementation is scoped and gated by existing preview permissions, but the new runtime behavior is not directly covered by tests, so human review is warranted.

No code changes detected at bcb7b21. Prior analysis still applies.

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[github-actions]

Thread transfer impact

⚠️ The latest CI run did not produce a thread transfer result for bcb7b21.

This comment will update automatically after the next completed run.

[cursor]

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[cursor]

Bugbot is paused — on-demand spend limit reached

Bugbot uses usage-based billing for this team and has hit its on-demand spend limit.

A team admin can raise the spend limit in the Cursor dashboard, or wait for the next billing cycle to continue.

[cursor]

Bugbot is paused — on-demand spend limit reached

Bugbot uses usage-based billing for this team and has hit its on-demand spend limit.

A team admin can raise the spend limit in the Cursor dashboard, or wait for the next billing cycle to continue.

[cursor]

Bugbot is paused — on-demand spend limit reached

Bugbot uses usage-based billing for this team and has hit its on-demand spend limit.

A team admin can raise the spend limit in the Cursor dashboard, or wait for the next billing cycle to continue.