fix: usage API rate-limit guard and cleanup debug logging

src/claude-usage.ts

@@ -58,13 +58,17 @@ function loadUsageDiskCache(): void {
     if (fs.existsSync(USAGE_CACHE_FILE)) {
       usageDiskCache = JSON.parse(fs.readFileSync(USAGE_CACHE_FILE, 'utf-8'));
     }
-  } catch { /* start fresh */ }
+  } catch {
+    /* start fresh */
+  }
 }
 
 function saveUsageDiskCache(): void {
   try {
     fs.writeFileSync(USAGE_CACHE_FILE, JSON.stringify(usageDiskCache));
-  } catch { /* best effort */ }
+  } catch {
+    /* best effort */
+  }
 }
 
 function cacheKey(token: string): string {
@@ -104,7 +108,9 @@ async function fetchUsageForToken(
       return null;
     }
     if (res.status === 429) {
-      logger.warn('Claude usage API: rate limited (429), returning cached data');
+      logger.warn(
+        'Claude usage API: rate limited (429), returning cached data',
+      );
       return usageDiskCache[cacheKey(token)]?.usage ?? null;
     }
     if (!res.ok) {

src/provider-fallback.ts

@@ -48,15 +48,13 @@ interface FallbackConfig {
 // ── State ────────────────────────────────────────────────────────
 
 let cooldown: CooldownState | null = null;
-let lastUsageAvailabilityCheck:
+let lastUsageAvailabilityCheck: {
-  | {
   checkedAt: number;
   result: 'available' | 'exhausted' | 'unknown';
-    }
+} | null = null;
-  | null = null;
+let usageAvailabilityCheckPromise: Promise<
-let usageAvailabilityCheckPromise:
+  'available' | 'exhausted' | 'unknown'
-  | Promise<'available' | 'exhausted' | 'unknown'>
+> | null = null;
-  | null = null;
 
 const USAGE_RECOVERY_RECHECK_MS = 30_000;
 
@@ -213,7 +211,10 @@ export async function getActiveProvider(): Promise<string> {
       }
       if (usageAvailability === 'exhausted') {
         // Current token exhausted — try rotating to another token (ignore cooldowns)
-        if (getTokenCount() > 1 && rotateToken(undefined, { ignoreRateLimits: true })) {
+        if (
+          getTokenCount() > 1 &&
+          rotateToken(undefined, { ignoreRateLimits: true })
+        ) {
           logger.info(
             'Claude current token exhausted, rotated to next token — retrying',
           );

src/token-rotation.ts

@@ -156,11 +156,7 @@ export function rotateToken(
   for (let i = 1; i < tokens.length; i++) {
     const idx = (currentIndex + i) % tokens.length;
     const state = tokens[idx];
-    if (
+    if (ignoreRL || !state.rateLimitedUntil || state.rateLimitedUntil <= now) {
-      ignoreRL ||
-      !state.rateLimitedUntil ||
-      state.rateLimitedUntil <= now
-    ) {
       state.rateLimitedUntil = null;
       currentIndex = idx;
       logger.info(