Add job application quick reference for storing profile links and experience

Auth-protected CRUD for personal info (LinkedIn, GitHub, etc.) and
experience entries, stored in the database so nothing sensitive is in
the public repo. Displayed as a categorized panel on the Job Applications page.

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

backend/services/database.go

@@ -39,6 +39,7 @@ func migrateDatabase(db *gorm.DB) error {
 		&models.Rowing{},
 		&models.Message{},
 		&models.JobApplication{},
+		&models.JobAppReference{},
 		&models.Bookmark{},
 	)
 	if err != nil {