feat(commit): 添加.gitignore文件过滤功能，自动跳过被忽略的文件

在自动暂存和`--all`模式下，检测并跳过被.gitignore规则匹配的文件，暂存完成后显示被移除的被忽略文件列表

src/git/mod.rs

@@ -533,27 +533,116 @@ impl GitRepo {
         Ok(files)
     }
 
-    /// Stage files
-    pub fn stage_files<P: AsRef<Path>>(&self, paths: &[P]) -> Result<()> {
+    /// Stage files, skipping paths matched by .gitignore rules
+    /// Returns the list of skipped paths (those matched by .gitignore)
+    pub fn stage_files<P: AsRef<Path>>(&self, paths: &[P]) -> Result<Vec<String>> {
         let mut index = self.repo.index()?;
+        let mut skipped = Vec::new();
 
         for path in paths {
             let path = path.as_ref();
-            if path.is_absolute() {
-                if let Ok(rel_path) = path.strip_prefix(&self.path) {
-                    index.add_path(rel_path)?;
+            let rel_path = if path.is_absolute() {
+                match path.strip_prefix(&self.path) {
+                    Ok(p) => p,
+                    Err(_) => {
+                        // Outside repo, skip
+                        skipped.push(path.to_string_lossy().to_string());
+                        continue;
+                    }
                 }
             } else {
-                index.add_path(path)?;
+                path
+            };
+
+            // Check if the path is ignored by .gitignore
+            if self.is_path_ignored(rel_path)? {
+                skipped.push(rel_path.to_string_lossy().to_string());
+                continue;
             }
+
+            index.add_path(rel_path)?;
         }
 
         index.write()?;
-        Ok(())
+        Ok(skipped)
     }
 
-    /// Stage all changes including subdirectories
-    pub fn stage_all(&self) -> Result<()> {
+    /// Check if a path is ignored by .gitignore rules
+    pub fn is_path_ignored<P: AsRef<Path>>(&self, path: P) -> Result<bool> {
+        let path = path.as_ref();
+
+        // Convert to relative path if absolute
+        let rel_path = if path.is_absolute() {
+            match path.strip_prefix(&self.path) {
+                Ok(p) => p,
+                Err(_) => return Ok(false), // Outside repo, not ignored
+            }
+        } else {
+            path
+        };
+
+        let path_str = match rel_path.to_str() {
+            Some(s) => s,
+            None => return Ok(false), // Non-UTF8 path, not ignored
+        };
+
+        let output = std::process::Command::new("git")
+            .args(["check-ignore", "--quiet", "--", path_str])
+            .current_dir(&self.path)
+            .output()?;
+
+        // Exit code 0: ignored, 1: not ignored, other: error
+        match output.status.code() {
+            Some(0) => Ok(true),
+            Some(1) => Ok(false),
+            _ => Ok(false), // Treat errors as not ignored
+        }
+    }
+
+    /// Remove files from index that are tracked but should be ignored by .gitignore
+    pub fn remove_ignored_from_index(&self) -> Result<Vec<String>> {
+        let output = std::process::Command::new("git")
+            .args(["ls-files", "--cached", "-i", "--exclude-standard"])
+            .current_dir(&self.path)
+            .output()?;
+
+        if !output.status.success() {
+            let stderr = String::from_utf8_lossy(&output.stderr);
+            bail!("Failed to list ignored tracked files: {}", stderr);
+        }
+
+        let stdout = String::from_utf8_lossy(&output.stdout);
+        let ignored_files: Vec<String> = stdout
+            .lines()
+            .map(|l| l.trim().to_string())
+            .filter(|l| !l.is_empty())
+            .collect();
+
+        if ignored_files.is_empty() {
+            return Ok(Vec::new());
+        }
+
+        // Remove these files from the index (keep working tree files)
+        let mut args = vec!["rm", "--cached", "--quiet", "--"];
+        for file in &ignored_files {
+            args.push(file);
+        }
+
+        let rm_output = std::process::Command::new("git")
+            .args(&args)
+            .current_dir(&self.path)
+            .output()?;
+
+        if !rm_output.status.success() {
+            let stderr = String::from_utf8_lossy(&rm_output.stderr);
+            bail!("Failed to remove ignored files from index: {}", stderr);
+        }
+
+        Ok(ignored_files)
+    }
+
+    /// Stage all changes including subdirectories, then remove ignored tracked files
+    pub fn stage_all(&self) -> Result<Vec<String>> {
         // Use git command for reliable staging (handles all edge cases)
         let output = std::process::Command::new("git")
             .args(["add", "-A"])
@@ -569,7 +658,14 @@ impl GitRepo {
         // Force refresh the git2 index to pick up changes from git CLI
         let _ = self.repo.index()?.write();
 
-        Ok(())
+        // Remove files that are tracked but should be ignored by .gitignore
+        match self.remove_ignored_from_index() {
+            Ok(removed) => Ok(removed),
+            Err(e) => {
+                eprintln!("Warning: failed to clean ignored files from index: {}", e);
+                Ok(Vec::new())
+            }
+        }
     }
 
     /// Unstage files