chore: include development database in git

- Add backend/prisma/dev.db to version control
- Update .gitignore to exclude all *.db files except backend/prisma/dev.db
- Update CI workflow to trigger on dev branch instead of master

Author: remotenwsshell

.github/workflows/ci.yml

@@ -2,9 +2,9 @@ name: CI
 
 on:
   push:
-    branches: [main, master]
+    branches: [main, dev]
   pull_request:
-    branches: [main, master]
+    branches: [main, dev]
 
 jobs:
   backend:

.gitignore

@@ -4,6 +4,7 @@ build/
 
 *.db
 *.db-journal
+!backend/prisma/dev.db
 
 .env
 .env.local