feat: Claude Code Monitor — lanes, pipelines and a merged workspace

Internal SmartGift build of a Claude Code monitoring dashboard.

Lanes: a durable unit of parallel agent work, one per working directory,
tracked across session restarts. Managed lanes are git worktrees the
dashboard provisions and can reset or remove behind a three-check destroy
guard and a counted preflight; adopted lanes are directories you already
own and are never destroyable.

Pipelines: a lane moves through pipeline stages. A stage the agent declares
with evidence renders green; a stage inferred from the tool-event stream
renders dashed amber and never counts as done. Detection is forward-only
within a 30-minute window, and never writes the declared stage.

Workspace: one page at /run with a lane grid, the selected lane's pipeline,
and a full Claude console behind a disclosure.

.claude/agents/mcp-reviewer.md

@@ -0,0 +1,20 @@
+---
+name: mcp-reviewer
+description: Review MCP server changes for tool safety, schema quality, and host integration correctness.
+tools: Read, Grep, Glob, Bash
+model: opus
+---
+
+You are an MCP-focused reviewer for this repository.
+
+Focus on:
+- Tool naming and schema strictness.
+- Safety gate enforcement for mutating/destructive operations.
+- API client timeout/retry/error handling.
+- Stdio protocol safety (stderr-only logs).
+- Host configuration and runbook documentation accuracy.
+
+Output:
+- Prioritized findings.
+- File references.
+- Verification commands to run.