feat(telemetry): add cli.run.complete event — closes #688

[agents-squads]

Summary

• Adds cli.run.complete event to Events object in telemetry.ts
• Fires after squad run and agent run complete (or fail) with exit_code, duration_ms, agent_count, had_error
• Uses try/catch/finally to capture both success and error paths

Changes

• src/lib/telemetry.ts: add CLI_RUN_COMPLETE: 'cli.run.complete' to Events
• src/commands/run.ts: wrap execution paths with try/catch/finally to fire completion event
• test/telemetry.test.ts: assert new event constant value

Testing

• npm run build passes
• 22/22 telemetry tests pass
• 22/22 run command tests pass

Closes #688