[WIP] Fix Altair embed options to remove actions (#7285)

- [x] Understand the problem: typecheck error in vega-component.tsx
- [x] Fix the type error for `actions` variable (line 251)
- [x] Run typecheck to verify the fix
- [x] Improve type assertion to include all action options
- [x] Reply to the comment with the fix

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frontend/src/plugins/impl/vega/vega-component.tsx

@@ -105,7 +105,7 @@ const LoadedVegaComponent = ({
   const actions = useMemo(() => {
     // If embedOptions contains 'actions', use it directly
     if (embedOptions && "actions" in embedOptions) {
-      return embedOptions.actions;
+      return embedOptions.actions as boolean | { export?: boolean; source?: boolean; compiled?: boolean; editor?: boolean } | undefined;
     }
 
     // Otherwise use defaults