Update .gitignore and refactor docker-compose.sh for improved host IP detection

- Added .host-ip to .gitignore to prevent tracking of host IP configurations.
- Enhanced docker-compose.sh to prioritize HOST_IP environment variable, fallback to .host-ip file, and finally auto-detect the host IP, improving robustness in various environments.
- Updated documentation to reflect changes in Supabase migration paths and removed references to deprecated management-dashboard-web-app directory.

supabase/.gitignore

@@ -0,0 +1,8 @@
+# Supabase
+.branches
+.temp
+
+# dotenvx
+.env.keys
+.env.local
+.env.*.local