Add OpenAI's GPT-5.3-Codex model support

[PeterDaveHello]

Description

This PR adds OpenAI Native provider support metadata for gpt-5.3-codex and adds focused unit coverage for model resolution.

What changed:

• Add gpt-5.3-codex to openAiNativeModels in packages/types/src/providers/openai.ts.
  • maxTokens: 128000
  • contextWindow: 400000
  • Tool support: apply_patch included, apply_diff and write_to_file excluded
  • Reasoning effort: low, medium, high, xhigh with default medium
  • Temperature: disabled
  • Prompt cache: enabled with 24h retention
  • Tiers: priority only (input: 3.5, output: 28, cacheReads: 0.35 per unit)
• Add coverage in src/api/providers/__tests__/openai-native.spec.ts for selecting gpt-5.3-codex via OpenAiNativeHandler#getModel().
  • Verifies model id
  • Verifies maxTokens and contextWindow
  • Verifies supportsReasoningEffort

Rationale:

• Ensure gpt-5.3-codex is resolvable through existing OpenAI Native model-path logic and that metadata stays aligned with current model configuration.

Test Procedure

Run:

pnpm --filter roo-cline exec vitest run api/providers/__tests__/openai-native.spec.ts

Result:

• Pass: 1 test file, 40 tests

Notes:

• I intentionally did not modify src/api/providers/__tests__/openai-native-usage.spec.ts to keep this PR scoped to native model registration + direct model lookup test coverage.

Pre-Submission Checklist

• Issue Linked: Link an approved issue (currently pending).
• Scope: Changes are focused on a single model support update.
• Self-Review: Diff reviewed for minimal and relevant impact.
• Testing: Added/updated test covers the new model path.
• Documentation Impact: Verify whether docs or model lists need updates.
• Contribution Guidelines: Contributor requirements reviewed.

Screenshots / Videos

Not applicable (no UI changes).

Documentation Updates

• No documentation updates are required.
• Yes, documentation updates are required. (Please update user-facing model docs if required.)

Interactively review PR in Roo Code Cloud

[hannesrudolph]

LGTM, changes are consistent with 5.2-codex pricing and structure.

[hannesrudolph]

Approved by Roo Ops on behalf of Hannes.