feature: merge conflict detection and resolution (#6)

- pulls now correctly identify merge conflicts and enter a merge state
- user resolves each file individually
- commit resolve merge state
- allows users to keep custom changes and pull in updates
- improve commit message component
- seperated commit / add functionality

backend/app/git/operations/pull.py

@@ -1,15 +1,49 @@
-# git/operations/pull.py
-
 import git
 import logging
+from git import GitCommandError
+from ..status.status import get_git_status
 
 logger = logging.getLogger(__name__)
 
+
 def pull_branch(repo_path, branch_name):
     try:
         repo = git.Repo(repo_path)
-        repo.git.pull('origin', branch_name)
-        return True, f"Successfully pulled changes for branch {branch_name}."
+
+        # Check for uncommitted changes first
+        if repo.is_dirty(untracked_files=True):
+            return False, {
+                'type': 'uncommitted_changes',
+                'message':
+                'Cannot pull: You have uncommitted local changes that would be lost',
+                'details': 'Please commit or stash your changes before pulling'
+            }
+
+        try:
+            # Fetch first to get remote changes
+            repo.remotes.origin.fetch()
+
+            try:
+                # Try to pull with explicit merge strategy
+                repo.git.pull('origin', branch_name, '--no-rebase')
+                return True, "Successfully pulled changes for branch {branch_name}"
+            except GitCommandError as e:
+                if "CONFLICT" in str(e):
+                    # Don't reset - let Git stay in merge conflict state
+                    return True, {
+                        'state': 'resolve',
+                        'type': 'merge_conflict',
+                        'message':
+                        'Repository is now in conflict resolution state. Please resolve conflicts to continue merge.',
+                        'details': 'Please resolve conflicts to continue merge'
+                    }
+                raise e
+
+        except GitCommandError as e:
+            logger.error(f"Git command error pulling branch: {str(e)}",
+                         exc_info=True)
+            return False, f"Error pulling branch: {str(e)}"
+
     except Exception as e:
         logger.error(f"Error pulling branch: {str(e)}", exc_info=True)
-        return False, f"Error pulling branch: {str(e)}"
+        return False, f"Error pulling branch: {str(e)}"