Add GET /status Endpoint for Deployment Queue State

[adarshm11]

Summary

There is currently no way to query the live state of the deployment server without reading logs. Adding a GET /status endpoint would expose which repos have active workers, whether queues are backed up, and the last deployment result for each repo.

Problem

When something goes wrong (e.g. a deployment is stuck or a queue is growing), there is no quick way to inspect the server state without ssh-ing in and tailing logs. A lightweight status endpoint would make it easy to check from a browser, curl, or a monitoring script.

Proposed Solution

Add a GET /status endpoint that returns a JSON snapshot of the current server state:

{
  "repos": {
    "my-repo/main": {
      "worker_active": true,
      "queue_depth": 2,
      "last_deployment": {
        "status": "success",
        "commit": "abc1234",
        "timestamp": "2026-03-24T10:15:00Z"
      }
    }
  }
}

Implementation notes:

• Worker thread state is already tracked in the workers dict — queue_depth can be derived from the existing Queue object.
• last_deployment can be stored in a small in-memory dict keyed by repo/branch, updated at the end of each worker run.
• No persistence needed — state resets on server restart.

Acceptance Criteria

• GET /status returns 200 OK with a JSON body
• Response includes each configured repo/branch, whether a worker is active, and queue depth
• Response includes the status, commit hash, and timestamp of the most recent completed deployment per repo
• Endpoint is documented in the README