Fix: Broken GitHub Rate Limit Detection and Graceful Exit

Problem

The rate limit detection implemented in #9083 is non-functional.

1. API Quota logs consistently show 5000/5000 (max) even when the limit is consumed.
2. The Updater service fails to exit when the limit is reached, causing cascading API rate limit already exceeded errors.

Root Cause Analysis

• The GitHub service relies solely on x-rate-limit-* headers.
• Logs indicate these headers are either missing, null, or not being parsed correctly in the current environment (likely due to fetch implementation differences or API quirks).
• Since rateLimit.remaining never updates, the "Graceful Exit" check (remaining < 50) in Updater.mjs never triggers.
• Additionally, Updater.mjs swallows rate limit errors in the processUser catch block, allowing the loop to continue hammering the API.

Proposed Solution

1. Robust Detection (GraphQL Body):

   • Modify Updater.mjs to request rateLimit { remaining limit resetAt } in all GraphQL queries.
   • Update GitHub.mjs to inspect json.data.rateLimit and update the internal state from the response body (primary source of truth for GraphQL).

2. Robust Detection (Headers):

   • Add logging to GitHub.mjs to debug why header parsing is failing (e.g., casing issues).

3. Fail-Safe Kill Switch:

   • Update Updater.mjs to detect "rate limit exceeded" errors in the catch block.
   • If detected, force GitHub.rateLimit.remaining = 0 and abort the batch immediately.

Tasks

• Modify apps/devrank/services/GitHub.mjs to parse data.rateLimit.
• Modify apps/devrank/services/Updater.mjs to include rateLimit field in queries.
• Add kill-switch logic to Updater.mjs.