chore: fix build warnings, add deployment config, and cleanup lint errors

- Fix React Hook dependencies and Image optimization warnings
- Add DATA_DIR and INITIAL_PASSWORD env var support
- Fix Tailwind v4 legacy syntax and suppress CSS directives warnings
- Add PropTypes and remove unused variables

.vscode/settings.json

@@ -0,0 +1,3 @@
+{
+  "css.lint.unknownAtRules": "ignore"
+}