feat: implement contact form submission and database integration

- Added a new collection for contact submissions with validation and error handling.
- Created a migration script to set up the contact submissions table in the database.
- Updated the SponsoringForm component to handle newsletter subscriptions based on application phase.
- Refactored the UI components for improved user experience and error messaging.
- Removed the package selection step from the sponsoring form.
- Updated the styling across various pages to maintain consistency with the new design.

src/migrations/index.ts

@@ -12,6 +12,7 @@ import * as migration_20260712_120000_partner_media_only from './20260712_120000
 import * as migration_20260713_133000_newsletter_form_and_subscriptions from './20260713_133000_newsletter_form_and_subscriptions';
 import * as migration_20260713_155500_shared_application_form from './20260713_155500_shared_application_form';
 import * as migration_20260713_163000_participation_supporting_awards_copy from './20260713_163000_participation_supporting_awards_copy';
+import * as migration_20260713_194500_contact_submissions from './20260713_194500_contact_submissions';
 
 export const migrations = [
   {
@@ -84,4 +85,9 @@ export const migrations = [
     down: migration_20260713_163000_participation_supporting_awards_copy.down,
     name: '20260713_163000_participation_supporting_awards_copy',
   },
+  {
+    up: migration_20260713_194500_contact_submissions.up,
+    down: migration_20260713_194500_contact_submissions.down,
+    name: '20260713_194500_contact_submissions',
+  },
 ];