Add .env and .env.example files; implement development script and Docker connection logic

src/main.rs

@@ -7,13 +7,22 @@ async fn main() -> anyhow::Result<()> {
 
     let folders = list_folders(backup_root_path).await?;
 
-    let docker_conn = Docker::connect_with_socket_defaults()?;
-    let docker_version = docker_conn.version().await?;
-    println!("Docker version: {:?}", docker_version);
+    let docker_host = std::env::var("DOCKER_HOST").ok();
+    let docker_conn = connect_docker(docker_host).await?;
+    
 
     Ok(())
 }
 
+async fn connect_docker(docker_host: Option<String>) -> anyhow::Result<Docker> {
+    Ok(
+        match docker_host {
+            Some(host) => Docker::connect_with_http(&host, 60, bollard::API_DEFAULT_VERSION)?,
+            None => Docker::connect_with_socket_defaults()?,
+        }
+    )
+}
+
 async fn list_folders(path: &std::path::Path) -> anyhow::Result<Vec<std::path::PathBuf>> {
     let mut folders = Vec::new();
     let mut dir_entries = tokio::fs::read_dir(path).await?;