fix: TypeScript errors for CI compatibility

- Exclude 'bypass' from updateEffect generic to fix spread type error
- Fix mock type annotation in Transport-xypad-sync.test.tsx

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: adewale

app/src/components/EffectsPanel.tsx

@@ -85,17 +85,18 @@ export function EffectsPanel({
     }
   }, []);
 
-  // Update a single effect parameter
-  const updateEffect = useCallback(<K extends keyof EffectsState>(
+  // Update a single effect parameter (excludes 'bypass' which is boolean, not an object)
+  const updateEffect = useCallback(<K extends Exclude<keyof EffectsState, 'bypass'>>(
     effectName: K,
     param: keyof EffectsState[K],
     value: number | string
   ) => {
     setEffects(prev => {
+      const prevEffect = prev[effectName] as Record<string, unknown>;
       const newEffects = {
         ...prev,
         [effectName]: {
-          ...prev[effectName],
+          ...prevEffect,
           [param]: value,
         },
       };

app/src/components/Transport-xypad-sync.test.tsx

@@ -38,7 +38,7 @@ vi.mock('../audio/engine', () => ({
  * It asserts the CORRECT behavior: XY pad should update BOTH wet and decay.
  */
 describe('Transport XY Pad Sync - EXPECTED BEHAVIOR', () => {
-  let onEffectsChange: ReturnType<typeof vi.fn>;
+  let onEffectsChange: (effects: EffectsState) => void;
   let capturedEffects: EffectsState[] = [];
 
   beforeEach(() => {
@@ -104,7 +104,7 @@ describe('Transport XY Pad Sync - EXPECTED BEHAVIOR', () => {
 });
 
 describe('Transport XY Pad Sync - FIXED BEHAVIOR', () => {
-  let onEffectsChange: ReturnType<typeof vi.fn>;
+  let onEffectsChange: (effects: EffectsState) => void;
   let capturedEffects: EffectsState[] = [];
 
   beforeEach(() => {

app/src/components/Transport.tsx

@@ -90,16 +90,18 @@ export function Transport({
   }, []);
 
   // Update a single effect parameter - syncs to server immediately
-  const updateEffect = useCallback(<K extends keyof EffectsState>(
+  // Excludes 'bypass' which is boolean, not an object with params
+  const updateEffect = useCallback(<K extends Exclude<keyof EffectsState, 'bypass'>>(
     effectName: K,
     param: keyof EffectsState[K],
     value: number | string
   ) => {
     // Compute new effects state
+    const currentEffect = effects[effectName] as Record<string, unknown>;
     const newEffects = {
       ...effects,
       [effectName]: {
-        ...effects[effectName],
+        ...currentEffect,
         [param]: value,
       },
     };