- No automatic IR1 requests; fragments arrive only when user taps load
- Bubble sends IR1 with missing indices only if partial session exists
(partial resume: only missing fragments requested, not the whole image)
- 30s timeout resets the loading spinner so user can tap retry again
- Saves LoRa airtime by never transmitting IR1 without explicit user action
- Replace 1.2s fixed retry with 10s idle debounce timer
- Timer resets on every received fragment (debounce)
- Timer also starts on IE1 envelope receipt (handles pull-only senders)
- IR1 always requests only missing indices (partial resume)
- Attempt counter no longer resets per fragment; bounded to 5 retries
- Max attempts raised to 5 (was 4)
