[EVAL] API key from Env Var support

[daniel-lxs]

🧪 Evaluation PR for Testing

This is an automated test PR created for evaluation purposes.

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Related GitHub Issue

Closes: #4337

Description

This PR adds support for obtaining API keys from the environment. A checkbox is added to each configuration that allows inputting an API key -- when checked, a given environment variable (eg, OPENAI_API_KEY, etc) is consulted for the key and the user is not required to provide one in the configuration. Env Var key is predictable but not editable.

Test Procedure

I tested this using VS Code run configurations, where the expected environment variable could be provided or omitted.

Pre-Submission Checklist

• Issue Linked: This PR is linked to an approved GitHub Issue (see "Related GitHub Issue" above).
• Scope: My changes are focused on the linked issue (one major feature/fix per PR).
• Self-Review: I have performed a thorough self-review of my code.
• Testing: New and/or updated tests have been added to cover my changes (if applicable).
• Documentation Impact: I have considered if my changes require documentation updates (see "Documentation Updates" section below).

A documentation update is advised, to describe environment variable usage to supply API keys.

• Contribution Guidelines: I have read and agree to the Contributor Guidelines.

Summary

Adds support for using environment variables for API keys across multiple providers, updates UI components to reflect this, and enhances testing and translation capabilities.

• Behavior:
  • Adds support for API keys from environment variables for providers like anthropic, glama, openrouter, openai, gemini, mistral, deepseek, unbound, requesty, xai, groq, chutes, litellm.
  • Updates validateModelsAndKeysProvided() to check for environment variable usage for API keys.
• UI Components:
  • Introduces ApiKey component to handle API key input and environment variable toggle.
  • Updates various provider components to use the new ApiKey component.
• Testing:
  • Adds comprehensive tests for environment variable integration and the ApiKey component.

[roo-code-dan]

I found a few issues that need to be addressed:

1. Typo in constant name: MOONSHOOT should be MOONSHOT in packages/types/src/constants.ts
2. Validation incompleteness: Missing environment variable checks in validation logic for newly supported providers (cerebras, sambanova, zai, fireworks, featherless, io-intelligence, vercel, doubao, moonshot, huggingface, deepinfra)

These issues will cause runtime failures when users try to use environment variables for API keys with the affected providers.

[roo-code-dan]

Typo: MOONSHOOT should be MOONSHOT to match the environment variable name MOONSHOT_API_KEY used throughout the codebase.

[roo-code-dan]

The constant reference uses API_KEYS.MOONSHOOT but the constant is misspelled in constants.ts (line 25). This will cause the environment variable lookup to fail at runtime since API_KEYS.MOONSHOOT resolves to 'MOONSHOT_API_KEY' but the constant name itself has a typo.

[roo-code-dan]

Missing validation updates for providers with new env var support. The PR adds *ConfigUseEnvVars flags for cerebras, sambanova, zai, fireworks, featherless, io-intelligence, vercel-ai-gateway, doubao, moonshot, huggingface, and deepinfra providers, but their validation cases (lines 62-65, 124-160) still require explicit API keys without checking the env var flags. These should follow the same pattern as anthropic (line 72), openrouter (line 42), etc. When the env var flag is enabled, validation should pass even without an explicit API key.