Init API Keys docs updates.
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> [!IMPORTANT]
> Add documentation and API handlers for creating and managing user and
team API keys.
>
> - **API Handlers**:
> - Updated `createApiKeyHandlers` in `handlers.tsx` to include metadata
for API key creation and validation.
> - `create` and `check` handlers now have descriptions, summaries, and
tags for API keys.
> - **Documentation**:
> - Added `api-keys.mdx` to explain API key creation, management, and
usage for users and teams.
> - Updated `docs-template.yml` to include API Keys in the navigation.
> - Added `sdk/types/api-key.mdx` for detailed API key type definitions
and usage.
> - Updated `sdk/types/team.mdx` and `sdk/types/user.mdx` to include API
key functions for teams and users.
>
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Co-authored-by: Konsti Wohlwend <n2d4xc@gmail.com>
