[Bug]: Contradicting information about env setup

[Alameyo]

Bug Description

We can't run the project on Vertex AI with the example environment configuration. I may be doing something wrong, but then it would require some clarification in the documentation

Steps to Reproduce

If you try to run cgr using this config

# Example 4: Google Vertex AI
# ORCHESTRATOR_PROVIDER=google
# ORCHESTRATOR_MODEL=gemini-2.5-pro
# ORCHESTRATOR_PROJECT_ID=your-gcp-project-id
# ORCHESTRATOR_REGION=us-central1
# ORCHESTRATOR_PROVIDER_TYPE=vertex
# ORCHESTRATOR_SERVICE_ACCOUNT_FILE=/path/to/service-account.json

# CYPHER_PROVIDER=google
# CYPHER_MODEL=gemini-2.5-flash
# CYPHER_PROJECT_ID=your-gcp-project-id
# CYPHER_REGION=us-central1
# CYPHER_PROVIDER_TYPE=vertex
# CYPHER_SERVICE_ACCOUNT_FILE=/path/to/service-account.json

Cgr will tell me I am missing GOOGLE_API_KEY env and even give me link where to get this API key

cgr start --repo-path /home/ubuntu/workspace/some-repo-i-am-testing

─── API Key Missing ───────────────────────────────────────────────

  Error: GOOGLE_API_KEY environment variable is not set.
         This is required to use Google AI for cypher.

  To fix this:

  1. Get your API key from:
     https://console.cloud.google.com/apis/credentials

  2. Set it in your environment:
     export GOOGLE_API_KEY='your-key-here'

     Or add it to your .env file in the project root:
     GOOGLE_API_KEY=your-key-here

  3. Alternatively, you can use a local model with Ollama:
     (No API key required)

however if I set up GOOGLE_API_KEY I will get error saying extra input is not allowed in envs.

Traceback (most recent call last):
  File "/home/ubuntu//code-graph-rag/.venv/bin/cgr", line 4, in <module>
    from codebase_rag.cli import app
  File "/home/ubuntu/code-graph-rag/codebase_rag/cli.py", line 12, in <module>
    from .config import load_cgrignore_patterns, settings
  File "/home/ubuntu/code-graph-rag/codebase_rag/config.py", line 325, in <module>
    settings = AppConfig()
               ^^^^^^^^^^^
  File "/home/ubuntu/code-graph-rag/.venv/lib/python3.12/site-packages/pydantic_settings/main.py", line 194, in __init__
    super().__init__(
  File "/home/ubuntu/code-graph-rag/.venv/lib/python3.12/site-packages/pydantic/main.py", line 250, in __init__
    validated_self = self.__pydantic_validator__.validate_python(data, self_instance=self)
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
pydantic_core._pydantic_core.ValidationError: 1 validation error for AppConfig
google_api_key
  Extra inputs are not permitted [type=extra_forbidden, input_value='I am not giving you my key :P', input_type=str]
    For further information visit https://errors.pydantic.dev/2.12/v/extra_forbidden

Expected Behavior

Should run project using credentials from the service account

Actual Behavior

Requests me some GOOGLE_API_KEY while also not running after providing one.

Error Logs

Programming Language

No response

Version

0.0.65

Operating System

Linux

Python Version

3.12.12

LLM Provider

Google Gemini

Additional Context

No response

Checklist

• I have searched existing issues to ensure this is not a duplicate
• I have included all relevant error logs and steps to reproduce
• I am using a supported version of Python (3.12+)