refactor(reading): increase debounce to 3 seconds

CHANGELOG.md

@@ -16,8 +16,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
-- Reading position auto-save now uses simple 2-second debounce
-  - Saves only after 2s of no scrolling (was 15s minimum interval)
+- Reading position auto-save now uses simple 3-second debounce
+  - Saves only after 3s of no scrolling (was 15s minimum interval)
   - Much less aggressive, reduces relay traffic
   - Still saves instantly at 100% completion
 

src/hooks/useReadingPosition.ts

@@ -70,7 +70,7 @@ export const useReadingPosition = ({
       clearTimeout(saveTimerRef.current)
     }
 
-    const DEBOUNCE_MS = 2000 // Save max every 2 seconds
+    const DEBOUNCE_MS = 3000 // Save max every 3 seconds
     console.log('[reading-position] ⏱️ Debouncing save for', DEBOUNCE_MS, 'ms (pos:', Math.round(currentPosition * 100) + '%)')
     saveTimerRef.current = setTimeout(() => {
       console.log('[reading-position] 💾 Auto-save at', Math.round(currentPosition * 100) + '%')