Document TrustedRouter provider setup

[jperla]

This pull request adds setup docs for TrustedRouter as an OpenAI-compatible provider in Continue. TrustedRouter is an open-source, verifiable attested router for privacy-sensitive workflows with zero prompt and output logging by default.

Users can connect through the existing OpenAI-compatible configuration by setting the base URL to https://api.trustedrouter.com/v1 and using standard model IDs such as trustedrouter/auto, trustedrouter/zdr, or trustedrouter/e2e.

Verification: git diff --check.

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Summary by cubic

Add documentation for configuring TrustedRouter as an OpenAI-compatible provider in Continue. Includes YAML/JSON examples, base URL https://api.trustedrouter.com/v1, and routing aliases (trustedrouter/auto, trustedrouter/zdr, trustedrouter/e2e); updates docs navigation.

^{Written for commit b674b4c. Summary will update on new commits.}

[github-actions]

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[cubic-dev-ai]

No issues found across 2 files

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