Handle Strava rate limiting with abort, retry time and daily usage display

Strava sync for 167 rides exceeds the 100/15-min read limit (2 calls per ride).
Previously a 429 was treated as a skipped ride, so every remaining ride also
failed silently. Now GetJSON returns a typed RateLimitError with RetryAfter
computed from Retry-After/Date and X-RateLimit headers (15-min window resets
at :00/:15/:30/:45, daily at midnight UTC) and tracks Read/Overall usage.
syncRides aborts on 429 with partial progress instead of skipping, and
handleSync emits an SSE error with retry time, daily usage vs limit and
structured rateLimit snapshot; progress and complete events also carry the
snapshot for the UI to display. Frontend shows Read daily/15-min usage in
progress details and on completion.

1 files changed, 16 insertions, 0 deletions

diff --git a/web/frontend/types.d.ts b/web/frontend/types.d.ts
index 3c2a918..6ff3dcf 100644
--- a/web/frontend/types.d.ts
+++ b/web/frontend/types.d.ts
@@ -124,14 +124,30 @@ export interface AnalyticsPoint {
   movingHours: number;
 }
 
+export interface RateLimit {
+  limit15: number;
+  usage15: number;
+  limitDaily: number;
+  usageDaily: number;
+}
+
+export interface RateLimitSnapshot {
+  read: RateLimit;
+  overall: RateLimit;
+}
+
 export interface SyncProgress {
   total: number;
   completed: number;
   imported: number;
   skipped: number;
+  rateLimit?: RateLimitSnapshot;
 }
 
 export interface SyncErrorEvent {
   message: string;
   progress?: SyncProgress;
+  retryAfter?: string;
+  isRateLimited?: boolean;
+  rateLimit?: RateLimitSnapshot;
 }