feat: add AUR repository support for Arch Linux packages

- Extended database schema and models to include 'aur' as a valid repository type alongside 'official' and 'third-party'
- Added repository filter UI in package browser for Arch platform to distinguish between official and AUR packages
- Enhanced init-db script with migration system to track and apply schema changes automatically

src/app/api/packages/route.ts

@@ -11,7 +11,7 @@ export async function GET(request: NextRequest) {
       category_id: searchParams.get('category_id') ? 
         parseInt(searchParams.get('category_id')!) : undefined,
       type: searchParams.get('type') as 'gui' | 'cli' | undefined,
-      repository: searchParams.get('repository') as 'official' | 'third-party' | undefined,
+      repository: searchParams.get('repository') as 'official' | 'third-party' | 'aur' | undefined,
       search: searchParams.get('search') || undefined,
       limit: searchParams.get('limit') ? 
         parseInt(searchParams.get('limit')!) : undefined,

src/app/api/sync-aur/route.ts

@@ -0,0 +1,52 @@
+import { NextRequest, NextResponse } from 'next/server'
+import { SyncAuth } from '@/lib/sync/auth'
+import { AurPackageFetcher } from '@/services/aurPackageFetcher'
+
+export const dynamic = 'force-dynamic'
+export const maxDuration = 300
+
+let syncInProgress = false
+let syncStatus: {
+  status: 'idle' | 'running' | 'complete' | 'error'
+  error: string | null
+} = { status: 'idle', error: null }
+
+export async function GET() {
+  return NextResponse.json(syncStatus)
+}
+
+export async function POST(request: NextRequest) {
+  const authResult = await SyncAuth.isSyncAllowed(request)
+  if (!authResult.allowed) {
+    return NextResponse.json(
+      { error: 'Sync operation not allowed', reason: authResult.reason },
+      { status: 403 }
+    )
+  }
+
+  if (syncInProgress) {
+    return NextResponse.json(
+      { error: 'Sync already in progress' },
+      { status: 409 }
+    )
+  }
+
+  syncInProgress = true
+  syncStatus = { status: 'running', error: null }
+
+  ;(async () => {
+    try {
+      const fetcher = new AurPackageFetcher()
+      const pkgs = await fetcher.fetchAllPackages()
+      await fetcher.storePackages(pkgs)
+      syncStatus.status = 'complete'
+    } catch (err: any) {
+      syncStatus.status = 'error'
+      syncStatus.error = err?.message || 'Unknown error'
+    } finally {
+      syncInProgress = false
+    }
+  })()
+
+  return NextResponse.json({ message: 'AUR sync started', status: syncStatus })
+}