feat: Add gitignore to init

assets/gitignore

@@ -0,0 +1 @@
+output/

src/site.rs

@@ -176,6 +176,16 @@ impl Site {
             let git_keep = statics_dir.join(".gitkeep");
             File::create(&git_keep).context(CreateDirectorySnafu { path: &git_keep })?;
         }
+        // Create the gitignore
+        let git_ignore_path = site_dir.join(".gitignore");
+        let mut git_ignore = File::create(&git_ignore_path).context(WriteConfigSnafu {
+            path: &git_ignore_path,
+        })?;
+        git_ignore
+            .write_all(include_bytes!("../assets/gitignore"))
+            .context(WriteConfigSnafu {
+                path: &git_ignore_path,
+            })?;
         Ok(())
     }
 }