Add branch creation and file history search

Implement the ability to create new local branches directly from the application's UI. This includes a new backend command to handle branch creation with validation and a frontend form in the branch panel.

Additionally, extend the global search dialog to include a "Files" tab. Users can now search for files by name or path within the repository. Selecting a file in the search results displays its full commit history, with options to diff the file at a specific commit or restore it to that version.

src-tauri/src/git.rs

@@ -281,6 +281,14 @@ pub fn checkout_branch(path: String, branch: String) -> Result<GitStatus, String
     status_for_repo(&repo)
 }
 
+#[tauri::command]
+pub fn create_branch(path: String, branch: String) -> Result<GitStatus, String> {
+    let repo = resolve_repo(&path)?;
+    let branch = validate_new_branch_name(&repo, &branch)?;
+    run_git(&repo, ["checkout", "-b", branch.as_str()])?;
+    status_for_repo(&repo)
+}
+
 #[tauri::command]
 pub fn stage_files(path: String, files: Vec<String>) -> Result<GitStatus, String> {
     let repo = resolve_repo(&path)?;
@@ -1839,6 +1847,38 @@ fn local_branch_name_for_remote(remote_branch: &str) -> Option<&str> {
         .filter(|local| !local.is_empty())
 }
 
+fn validate_new_branch_name(repo: &Path, branch: &str) -> Result<String, String> {
+    let branch = branch.trim();
+    if branch.is_empty() {
+        return Err("Branch-Name darf nicht leer sein.".to_string());
+    }
+
+    let output = git_command()
+        .arg("-C")
+        .arg(repo)
+        .args(["check-ref-format", "--branch", branch])
+        .output()
+        .map_err(|err| format!("Git konnte nicht gestartet werden. Ist Git installiert? {err}"))?;
+
+    if !output.status.success() {
+        let details = command_output_details(&output);
+        return Err(format!("Ungueltiger Branch-Name: {details}"));
+    }
+
+    let normalized = String::from_utf8_lossy(&output.stdout).trim().to_string();
+    let normalized = if normalized.is_empty() {
+        branch.to_string()
+    } else {
+        normalized
+    };
+
+    if ref_exists(repo, &format!("refs/heads/{normalized}"))? {
+        return Err(format!("Branch '{normalized}' existiert bereits."));
+    }
+
+    Ok(normalized)
+}
+
 fn ref_exists(repo: &Path, ref_name: &str) -> Result<bool, String> {
     let output = git_command()
         .arg("-C")
@@ -3186,6 +3226,31 @@ mod tests {
         assert_eq!(plan, CheckoutPlan::Local("feature/demo".to_string()));
     }
 
+    #[test]
+    fn create_branch_creates_and_checks_out_local_branch() {
+        let repo = init_temp_repo("create_branch");
+        commit_initial_file(&repo.path);
+
+        let status = create_branch(
+            repo.path.to_string_lossy().to_string(),
+            "feature/new-panel".to_string(),
+        )
+        .unwrap();
+
+        assert_eq!(status.current_branch.as_deref(), Some("feature/new-panel"));
+        assert!(
+            ref_exists(&repo.path, "refs/heads/feature/new-panel").unwrap(),
+            "new branch should exist"
+        );
+
+        let err = create_branch(
+            repo.path.to_string_lossy().to_string(),
+            "feature/new-panel".to_string(),
+        )
+        .unwrap_err();
+        assert!(err.contains("existiert bereits"));
+    }
+
     #[test]
     fn restore_to_commit_resets_branch_to_selected_commit() {
         let repo = init_temp_repo("restore_to_commit");

src-tauri/src/main.rs

@@ -4,11 +4,11 @@ mod git;
 
 use git::{
     cancel_code_search, checkout_branch, commit, compare_commits, compare_file_to_head,
-    compare_file_to_parent, cred_delete, cred_load, cred_save, diff_file_against_working_tree,
-    get_remote_url, get_status, list_branches, list_commits, list_file_history,
-    list_repository_files, merge_branch, open_repository, pull, push, read_conflict,
-    resolve_conflict, resolve_conflict_side, restore_file_from_commit, restore_files,
-    restore_to_commit, search_code_introductions, stage_files, unstage_files,
+    compare_file_to_parent, create_branch, cred_delete, cred_load, cred_save,
+    diff_file_against_working_tree, get_remote_url, get_status, list_branches, list_commits,
+    list_file_history, list_repository_files, merge_branch, open_repository, pull, push,
+    read_conflict, resolve_conflict, resolve_conflict_side, restore_file_from_commit,
+    restore_files, restore_to_commit, search_code_introductions, stage_files, unstage_files,
     SearchCancellationState,
 };
 
@@ -22,6 +22,7 @@ fn main() {
             get_status,
             list_branches,
             checkout_branch,
+            create_branch,
             stage_files,
             unstage_files,
             restore_files,