refactor(scanner): type the worker path and align app-test results

Move the worker scanner surface into TypeScript, add a direct worker regression, and make the version=2 app-test path populate the same visible result data and final status as the legacy scanner. This keeps the refactor bounded while making the worker route safe to exercise.

Constraint: Must preserve the existing Apple Silicon app-test behavior while changing the worker internals
Rejected: Flip production to the worker path immediately | still needs the normal deploy path and broader production soak
Confidence: medium
Scope-risk: moderate
Reversibility: clean
Directive: Keep the version=2 adapter using the shared finishFileScan path until the legacy scanner can be removed entirely
Tested: pnpm run typecheck; pnpm exec vitest run test/scanner/client.test.ts; pnpm run test:browser (original workspace); netlify build --context deploy-preview (original workspace)
Not-tested: Browser suite from the clean clone environment (local Astro dev server startup timed out there)

test/scanner/client.test.ts

@@ -0,0 +1,48 @@
+import {
+    describe,
+    expect,
+    it
+} from 'vitest'
+import '@vitest/web-worker'
+
+import { runScanWorker } from '~/helpers/scanner/client'
+
+import { createNativeAppArchive } from '../playwright/support/app-archive-fixture'
+
+describe( 'scanner worker client', () => {
+    it( 'extracts app metadata from a zipped native app fixture', async () => {
+        const progressMessages: string[] = []
+        const archiveFile = await createNativeAppArchive()
+
+        const { scan } = await runScanWorker( archiveFile, details => {
+            if ( typeof details.message === 'string' ) {
+                progressMessages.push( details.message )
+            }
+        } )
+
+        expect( progressMessages ).toContain( 'ℹ️ Found Info.plist' )
+        expect( scan.status ).toBe( 'finished' )
+        expect( scan.displayName ).toBe( 'Playwright Native App' )
+        expect( scan.appVersion ).toBe( '1.0.0' )
+        expect( scan.binarySupportsNative ).toBe( true )
+        expect( scan.displayBinarySize.length ).toBeGreaterThan( 0 )
+        expect( scan.details ).toEqual( expect.arrayContaining( [
+            expect.objectContaining({
+                label: 'Bundle Identifier',
+                value: 'com.doesitarm.playwright-native-app'
+            }),
+            expect.objectContaining({
+                label: 'Version',
+                value: '1.0.0'
+            })
+        ] ) )
+        expect( scan.info.filename ).toBe( 'Playwright Native App.app.zip' )
+        expect( scan.info.result ).toBe( '✅' )
+        expect( scan.info.infoPlist.CFBundleIdentifier ).toBe( 'com.doesitarm.playwright-native-app' )
+        expect( scan.info.machoMeta.architectures ).toEqual( expect.arrayContaining( [
+            expect.objectContaining({
+                processorType: 'ARM64'
+            })
+        ] ) )
+    } )
+} )