Fix Goal submissions with swarm mode - #131

Submitting Goal together with a swarm selection dropped the selected mode, and a successful submission from the home screen could leave the submitted text in the composer. Apply the selected swarm mode before executing Goal, route home submissions through the shared sender, and clear only the matching accepted draft. Failed submissions and edits made while a request is pending remain intact. Explicit /swarm commands now use the built-in command endpoint.

Adds regression coverage for command ordering, mesh/star/off, failure handling, navigation order, and Goal continuation with mesh context and tools. Design and acceptance notes are in openspec/changes/add-mesh-swarm-mode/.

Integrated onto v1.0.6 (e090be90) after reviewing the overlapping ChatView.jsx changes. Existing local Computer Use work is excluded.

Validation on the integrated tree:

• pnpm test: 3176 pass markers plus 3 passing Node test runner cases.
• pnpm build, including the regex compatibility check.
• OpenSpec strict validation, layer/include/file-size/ownership/document-path checks, and git diff --check.
• Syntax compilation of the new C++ Goal regression against the integrated source.

The focused C++ regression AgentLoopGoal.MeshToolsAndContextRemainAvailableDuringGoalContinuation passed on macOS before remote integration; the native runtime test was not rerun after integration, and the full native suite was not run locally.