refactor: rename database → storage

More semantically accurate: contains SQLite files, schema, fixtures, test data.
Updated all references in code, scripts, docs.

docs/DATABASE_CONFIG.md

@@ -23,10 +23,10 @@ The `shared/config.php` file defines:
 
 ```php
 // Test database (development)
-DB_TEST_PATH = '/path/to/database/test.db'
+DB_TEST_PATH = '/path/to/storage/test.db'
 
 // Production database (server)
-DB_PROD_PATH = '/path/to/database/posterg.db'
+DB_PROD_PATH = '/path/to/storage/posterg.db'
 ```
 
 ## How It Works
@@ -35,7 +35,7 @@ DB_PROD_PATH = '/path/to/database/posterg.db'
 
 By default, the system automatically determines which database to use:
 
-1. **If `database/test.db` exists** → Use test database (development mode)
+1. **If `storage/test.db` exists** → Use test database (development mode)
 2. **Otherwise** → Use production database (production mode)
 
 This means:
@@ -123,7 +123,7 @@ just deploy-database
 To test with production data locally:
 ```bash
 # Download production database (optional)
-scp posterg:/var/www/html/database/posterg.db database/
+scp posterg:/var/www/html/storage/posterg.db database/
 
 # Remove test database to force production mode
 rm database/test.db
@@ -177,5 +177,5 @@ if (isTestMode()) {
 - **Explicit test deploy**: Use `just test-deploy` to explicitly deploy test.db when needed
 - **Git ignored**: Test database is in `.gitignore` and never committed
 - **Backups**: Production database should be backed up regularly
-- **Schema**: Both databases use the same schema (`database/schema.sql`)
+- **Schema**: Both databases use the same schema (`storage/schema.sql`)
 - **Verification**: Run `rsync --dry-run` to preview what will be deployed before deploying