Fix race conditions from unawaited async forEach callbacks

[Copilot]

The async callbacks in forEach loops weren't being awaited, causing race conditions in package cache construction and dependency graph building.

Changes

• Replaced async forEach with for...of loops: Ensures synchronous execution where package cache and dependency relationships must complete before proceeding
• Updated control flow: Changed return to continue for loop contexts
• Added type safety: Introduced TopLevelReferrer type and replaced empty array types [] with proper types (TopLevelReferrer[], string[])

Example

// Before - async callback not awaited
componentsFound.forEach(async (component: any) => {
  const pkg = new ComponentDetectionPackage(...);
  packageCache.addPackage(pkg);
  return; // early exit
});

// After - synchronous for...of loop
for (const component of componentsFound) {
  const pkg = new ComponentDetectionPackage(...);
  packageCache.addPackage(pkg);
  continue; // early exit
}

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