⬆️ chore(Cargo.toml)：升级版本号至0.1.7

♻️ refactor(changelog.rs)：移除prepend参数，改为自动前置到现有changelog
♻️ refactor(formatter.rs)：移除未使用的日期和格式化函数
♻️ refactor(validators.rs)：移除未使用的SSH密钥验证功能

src/commands/changelog.rs

@@ -39,10 +39,6 @@ pub struct ChangelogCommand {
     #[arg(short, long)]
     generate: bool,
 
-    /// Prepend to existing changelog
-    #[arg(short, long)]
-    prepend: bool,
-
     /// Include commit hashes
     #[arg(long)]
     include_hashes: bool,
@@ -162,13 +158,34 @@ impl ChangelogCommand {
             }
         }
 
-        // Write to file
-        if self.prepend && output_path.exists() {
+        // Write to file (always prepend to preserve history)
+        if output_path.exists() {
             let existing = std::fs::read_to_string(&output_path)?;
-            let new_content = format!("{}\n{}", changelog, existing);
+            let new_content = if existing.is_empty() {
+                format!("# Changelog\n\n{}", changelog)
+            } else {
+                let lines: Vec<&str> = existing.lines().collect();
+                let mut header_end = 0;
+                
+                for (i, line) in lines.iter().enumerate() {
+                    if i == 0 && line.starts_with('#') {
+                        header_end = i + 1;
+                    } else if line.trim().is_empty() {
+                        header_end = i + 1;
+                    } else {
+                        break;
+                    }
+                }
+                
+                let header = lines[..header_end].join("\n");
+                let rest = lines[header_end..].join("\n");
+                
+                format!("{}\n{}\n{}", header, changelog, rest)
+            };
             std::fs::write(&output_path, new_content)?;
         } else {
-            std::fs::write(&output_path, changelog)?;
+            let content = format!("# Changelog\n\n{}", changelog);
+            std::fs::write(&output_path, content)?;
         }
 
         println!("{} {:?}", messages.changelog_written(), output_path);