refactor: implement scalable asset manifest system for dynamic images

Created build-time script to generate TypeScript manifest from public/assets, avoiding import.meta.glob limitations. Images stay in public/ for scalability (supports hundreds), while components get type-safe auto-discovery. Manifest auto-regenerates before builds.

scripts/generate-asset-manifest.js

@@ -0,0 +1,38 @@
+import { readdirSync, writeFileSync, mkdirSync } from 'fs';
+import { join, dirname } from 'path';
+import { fileURLToPath } from 'url';
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = dirname(__filename);
+const publicDir = join(__dirname, '..', 'public');
+
+// Scan for banners
+const bannersDir = join(publicDir, 'assets', 'banners');
+const banners = readdirSync(bannersDir)
+  .filter((file) => /^banner-.*\.(jpg|jpeg|gif|png)$/i.test(file))
+  .map((file) => `assets/banners/${file}`);
+
+// Scan for not-found images
+const notFoundDir = join(publicDir, 'assets', 'not-found');
+const notFoundImages = readdirSync(notFoundDir)
+  .filter((file) => /^not-found-.*\.(jpg|jpeg|gif|png)$/i.test(file))
+  .map((file) => `assets/not-found/${file}`);
+
+// Generate TypeScript file
+const output = `// Auto-generated file - do not edit manually
+// Run 'node scripts/generate-asset-manifest.js' to regenerate
+// This file is generated from public/assets/ directory
+
+export const BANNERS = ${JSON.stringify(banners, null, 2)} as const;
+
+export const NOT_FOUND_IMAGES = ${JSON.stringify(notFoundImages, null, 2)} as const;
+`;
+
+// Ensure directory exists
+const generatedDir = join(__dirname, '..', 'src', 'generated');
+mkdirSync(generatedDir, { recursive: true });
+
+const outputPath = join(generatedDir, 'asset-manifest.ts');
+writeFileSync(outputPath, output, 'utf8');
+
+console.log(`✅ Generated asset manifest with ${banners.length} banners and ${notFoundImages.length} not-found images`);