feat(minecraft): add rate limit detection and backoff to brain retry logic

Add isRateLimitError helper to detect 429 status and rate limit messages, implement 500ms sleep on rate limit errors before retry

Author: shinohara-rin

services/minecraft/src/cognitive/conscious/brain.ts

@@ -58,6 +58,17 @@ function isLikelyAuthOrBadArgError(err: unknown): boolean {
   )
 }
 
+function isRateLimitError(err: unknown): boolean {
+  const status = getErrorStatus(err)
+  if (status === 429) return true
+  const msg = toErrorMessage(err).toLowerCase()
+  return msg.includes('rate limit') || msg.includes('too many requests')
+}
+
+function sleep(ms: number): Promise<void> {
+  return new Promise(resolve => setTimeout(resolve, ms))
+}
+
 
 interface BrainResponse {
   action: ActionInstruction & { id?: string }
@@ -257,13 +268,18 @@ export class Brain {
         break // Success, exit retry loop
       } catch (err) {
         const remaining = maxAttempts - attempt
+        const isRateLimit = isRateLimitError(err)
         const shouldRetry = remaining > 0 && !isLikelyAuthOrBadArgError(err)
-        this.deps.logger.withError(err).error(`Brain: Decision attempt failed (attempt ${attempt}/${maxAttempts}, retry: ${shouldRetry})`)
+        this.deps.logger.withError(err).error(`Brain: Decision attempt failed (attempt ${attempt}/${maxAttempts}, retry: ${shouldRetry}, rateLimit: ${isRateLimit})`)
 
         if (!shouldRetry) {
           throw err // Re-throw if we can't retry
         }
-        // Otherwise continue to next attempt
+
+        // Backoff on rate limit (429)
+        if (isRateLimit) {
+          await sleep(500)
+        }
       }
     }