feat(cli): add codemie models list command (EPMCDME-11631)

[TarasSpashchenko]

Summary

Adds a new codemie models list CLI command that displays all AI models available to the user based on their current provider/auth configuration. Resolves EPMCDME-11631.

Changes

• New command codemie models list — loads the active profile via ConfigLoader, resolves the provider's ProviderModelFetcher through ProviderRegistry.getModelProxy(), and prints a formatted table of model ID, name, and description
• Bedrock fix — BedrockModelProxy.fetchModels() now honours runtime config fields (awsRegion, awsProfile, apiKey, awsSecretAccessKey) instead of the hardcoded singleton defaults, so users with non-default regions or profiles get correct results
• LiteLLM fix — LiteLLMModelProxy is now registered in litellm/index.ts; fetchModels() uses config.baseUrl and config.apiKey so the runtime profile values are respected
• Error messages — distinct messages for "no provider configured" vs "provider does not support model listing"

Impact

Before: no way to discover available models without leaving the CLI.

After:

$ codemie models list

Provider: litellm

ID                                       NAME                               DESCRIPTION
claude-3-5-sonnet                        claude-3-5-sonnet                  ...
gpt-4o                                   gpt-4o                             ...

2 model(s) available.

Supported providers: Ollama, AWS Bedrock, LiteLLM, CodeMie SSO (ai-run-sso).

Checklist

• Self-reviewed
• Manual testing performed
• Documentation updated (if needed)
• No breaking changes (or clearly documented)