Add daily automatic database backup to GitHub

- Remove data/ from .gitignore (keep WAL/SHM excluded)
- Add backup.sh script: commits and pushes DB changes daily
- Cron job at 3:00 AM: /var/www/html/dispensa/backup.sh
- Include initial database snapshot

backup.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+# Daily backup of Dispensa database to GitHub
+# Runs via cron: commits and pushes data/dispensa.db
+
+cd /var/www/html/dispensa || exit 1
+
+# Only commit if there are actual changes
+if git diff --quiet data/ 2>/dev/null && git diff --cached --quiet data/ 2>/dev/null; then
+    # Check for untracked files in data/
+    if [ -z "$(git ls-files --others --exclude-standard data/)" ]; then
+        exit 0  # Nothing changed
+    fi
+fi
+
+DATE=$(date '+%Y-%m-%d %H:%M')
+git add data/dispensa.db
+git commit -m "📦 Backup database automatico - $DATE"
+git push