feat(codecompanion): use free model

Author: chrishrb

modules/common/nvim/prompts/commit.md

@@ -3,6 +3,9 @@ name: Commit message
 interaction: chat
 description: Generate a commit message
 opts:
+  adapter:
+    name: copilot
+    model: gpt-4.1
   alias: commit
   auto_submit: false
   is_slash_cmd: true