feat: add effect parameter automation and fix mode logic

Completed Phase 9.3 - Full Automation Playback:
- ✅ Effect parameter automation implementation
- ✅ Fixed automation mode logic (now applies in all modes)
- ✅ Automatic parameter range conversion (normalized to actual values)

Effect parameter automation:
- Parses effect parameter IDs (format: effect.{effectId}.{paramName})
- Finds corresponding effect nodes in audio graph
- Converts normalized 0-1 automation values to actual parameter ranges
- Applies parameters using updateEffectParameters during playback
- Works with all effect types (filters, dynamics, time-based, etc.)

Automation mode fix:
- Removed incorrect mode !== 'read' checks
- Automation now plays back in all modes (read/write/touch/latch)
- Mode will control recording behavior, not playback

Technical notes:
- Used type assertion (as any) for dynamic parameter updates
- Maintains parameter range from automation lane valueRange
- Integrated with existing effect update mechanism

Phase 9 Status:
✅ 9.1: Automation lanes UI complete
✅ 9.2: Automation points complete
✅ 9.3: Real-time playback (volume, pan, effects) complete
⏳ 9.3: Automation recording (next milestone)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

lib/hooks/useMultiTrackPlayer.ts

@@ -110,7 +110,7 @@ export function useMultiTrackPlayer(tracks: Track[], masterVolume: number = 1) {
     tracks.forEach((track, index) => {
       // Apply volume automation
       const volumeLane = track.automation.lanes.find(lane => lane.parameterId === 'volume');
-      if (volumeLane && volumeLane.points.length > 0 && volumeLane.mode !== 'read') {
+      if (volumeLane && volumeLane.points.length > 0) {
         const automatedValue = evaluateAutomationLinear(volumeLane.points, currentTime);
         if (automatedValue !== undefined && gainNodesRef.current[index]) {
           const trackGain = getTrackGain(track, tracks);
@@ -124,7 +124,7 @@ export function useMultiTrackPlayer(tracks: Track[], masterVolume: number = 1) {
 
       // Apply pan automation
       const panLane = track.automation.lanes.find(lane => lane.parameterId === 'pan');
-      if (panLane && panLane.points.length > 0 && panLane.mode !== 'read') {
+      if (panLane && panLane.points.length > 0) {
         const automatedValue = evaluateAutomationLinear(panLane.points, currentTime);
         if (automatedValue !== undefined && panNodesRef.current[index]) {
           // Pan automation values are 0-1, but StereoPannerNode expects -1 to 1
@@ -136,7 +136,39 @@ export function useMultiTrackPlayer(tracks: Track[], masterVolume: number = 1) {
         }
       }
 
-      // TODO: Apply effect parameter automation
+      // Apply effect parameter automation
+      track.automation.lanes.forEach(lane => {
+        // Check if this is an effect parameter (format: effect.{effectId}.{parameterName})
+        if (lane.parameterId.startsWith('effect.') && lane.points.length > 0) {
+          const parts = lane.parameterId.split('.');
+          if (parts.length === 3) {
+            const effectId = parts[1];
+            const paramName = parts[2];
+
+            // Find the effect in the track's effect chain
+            const effectIndex = track.effectChain.effects.findIndex(e => e.id === effectId);
+            if (effectIndex >= 0 && effectNodesRef.current[index] && effectNodesRef.current[index][effectIndex]) {
+              const automatedValue = evaluateAutomationLinear(lane.points, currentTime);
+              if (automatedValue !== undefined) {
+                const effectNodeInfo = effectNodesRef.current[index][effectIndex];
+
+                // Convert normalized 0-1 value to actual parameter range
+                const effect = track.effectChain.effects[effectIndex];
+                const actualValue = lane.valueRange.min + (automatedValue * (lane.valueRange.max - lane.valueRange.min));
+
+                // Update the effect parameter
+                if (effect.parameters) {
+                  const updatedParams = { ...effect.parameters, [paramName]: actualValue } as any;
+                  updateEffectParameters(audioContextRef.current!, effectNodeInfo, {
+                    ...effect,
+                    parameters: updatedParams
+                  });
+                }
+              }
+            }
+          }
+        }
+      });
     });
 
     automationFrameRef.current = requestAnimationFrame(applyAutomation);