refactor: clean up codebase, remove dead code and obsolete docs

Remove influencer-era documentation, unused components, boilerplate
assets, and ghost tiktok cron job. Add supplier invoice management,
document API routes, and PWA icons. Replace boilerplate README.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/api/banking/connect/route.ts

@@ -65,7 +65,7 @@ export async function POST(request: Request) {
       .from('bank_connections')
       .insert({
         user_id: user.id,
-        bank_id: `${aspsp_name.toLowerCase().replace(/\s+/g, '-')}-${aspsp_country.toLowerCase()}`,
+        provider: `${aspsp_name.toLowerCase().replace(/\s+/g, '-')}-${aspsp_country.toLowerCase()}`,
         bank_name: aspsp_name,
         authorization_id,
         status: 'pending',