refactor: Improve backup-env-files.sh for temp file handling and enhance crontab entries for .env backups

docs/env-backup-system.md

@@ -207,6 +207,7 @@ The system automatically finds:
 ### Common Issues
 
 1. **Git Push Fails**
+
    ```bash
    # Check remote URL
    cd ~/.env-backup && git remote -v
@@ -216,6 +217,7 @@ The system automatically finds:
    ```
 
 2. **Missing Files**
+
    ```bash
    # List what would be found
    ./backup-env-files.sh --list
@@ -279,12 +281,14 @@ git status --porcelain
 ### Additional Security Measures
 
 1. **GPG Encryption** (Optional)
+
    ```bash
    # Encrypt sensitive files before committing
    gpg --symmetric --cipher-algo AES256 file.env
    ```
 
 2. **Restricted Permissions**
+
    ```bash
    # Secure backup directory
    chmod 700 ~/.env-backup
@@ -292,6 +296,7 @@ git status --porcelain
    ```
 
 3. **Audit Trail**
+
    ```bash
    # Monitor repository access
    git log --oneline --graph --all