Refactor Dockerfile and add linguist module

This commit refactors the Dockerfile to:
- Reintroduce the programmer user creation with sudo privileges
- Add necessary system dependencies for development tools
- Update Go installation to include PATH in root's bashrc
- Install github-linguist gem

It also includes the addition of a new linguist command module with functions to interact with GitHub Linguist for language statistics and file information retrieval.

old/test.py

@@ -0,0 +1,7 @@
+import requests
+
+url = "http://localhost:6666"  # point d'entrée principal
+payload = {"tool": "echo", "input": {"text": "Bonjour MCP!"}}
+
+resp = requests.post(url, json=payload)
+print(resp.json())  # {"echo": "Bonjour MCP!"} attendu