feat: upgrade default LLM to Pro when --deep flag is used and update CI Python versions to include 3.10.

Author: lguibr

.github/workflows/main.yml

@@ -15,7 +15,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.9", "3.11", "3.12"]
+        python-version: ["3.10", "3.11", "3.12"]
 
     steps:
     - name: Check out code

commitai/cli.py

@@ -206,12 +206,11 @@ def generate_message(
     # 2. If --deep is passed, upgrade to gemini-3-pro-preview
     # (unless -m is explicitly distinct)
     if deep:
-        # If user didn't explicitly change the default model string,
-        # upgrade to Pro
-        # If user explicitly set a model AND used --deep,
-        # we respect the explicit model but could warn (or just use it)
-        pass
-        pass
+        # Upgrade to Pro model if deep flag is set
+        # We override the model unless the user explicitly chose a different one
+        # (For simplicity here, we assume --deep implies pro)
+        if model == "gemini-3-flash-preview":
+            model = "gemini-3-pro-preview"
 
     llm = _initialize_llm(model)