[FEATURE] Add API key reconfiguration Cortex Wizard

[Suyashd999]

Description

Implement functionality in cortex wizard to allow users to reconfigure their API keys and provider preferences after initial setup.

Current Behavior

When running any Cortex command without an API key configured, the wizard prompts the user to add one. However, once configured, there is no way to reconfigure or change the API key or provider preference.

Proposed Behavior

• Allow users to update or replace existing API keys at any time
• Enable switching between supported LLM providers:
  • OpenAI
  • Anthropic
  • Ollama (for local execution)
• Provide an option to view/validate current configuration
• Enable reconfiguration without requiring manual ENV variable changes

Use Case

Users may need to:

• Change their API key
• Switch between cloud providers (OpenAI ↔ Anthropic)
• Move to local execution with Ollama

Currently, there's no streamlined way to reconfigure these settings through the wizard once they're set.

[jaysurse]

working on it -effiti