fix: include frontend dist assets in repo, fix deploy.sh syntax

- Remove .gitignore exclusion for dist/assets/ and frontend/dist/
- Fix deploy.sh: add missing quote on echo line
- Fix deploy.sh: correct ADMIN_PASSWORD=*** syntax
- Make deploy.sh auto-detect go/npm availability

.gitignore

@@ -6,8 +6,6 @@ backend/data/
 
 # 编译产物
 backend/autossl
-backend/dist/assets/
-frontend/dist/
 node_modules/
 
 # IDE