Skip gem RBI regeneration when lockfile clean

Only regenerate RBIs when Gemfile.lock has uncommitted changes in git,
which targets manual bundle updates. This improves performance by avoiding
unnecessary regeneration during normal git operations.

lib/ruby_lsp/tapioca/addon.rb

@@ -47,7 +47,7 @@ def activate(global_state, outgoing_queue)
           outgoing_queue << Notification.window_log_message("Activating Tapioca add-on v#{version}")
           @rails_runner_client.register_server_addon(File.expand_path("server_addon.rb", __dir__))
 
-          check_gemfile_changes
+          handle_gemfile_changes
         rescue IncompatibleApiError
           # The requested version for the Rails add-on no longer matches. We need to upgrade and fix the breaking
           # changes
@@ -114,7 +114,17 @@ def workspace_did_change_watched_files(changes)
       private
 
       sig { void }
-      def check_gemfile_changes
+      def handle_gemfile_changes
+        return unless File.exist?(".git")
+
+        gemfile_status = %x(git status --porcelain Gemfile.lock).strip
+        return if gemfile_status.empty?
+
+        process_gemfile_changes
+      end
+
+      sig { returns(T.nilable(Integer)) }
+      def process_gemfile_changes
         current_lockfile = File.read("Gemfile.lock")
         snapshot_lockfile = File.read(GEMFILE_LOCK_SNAPSHOT) if File.exist?(GEMFILE_LOCK_SNAPSHOT)