fix(openai): allow available Codex OAuth models

[steipete]

Summary

• Remove stale OpenAI/Codex suppressions for available GPT-5.1, GPT-5.2, and GPT-5.3 model refs.
• Keep removed Spark aliases suppressed.
• Update config validation, model catalog, runtime tests, docs, and changelog for [Bug]: gpt-5.3-codex is no longer supported for ChatGPT/Codex OAuth accounts #83303.

Fixes #83303

Verification

• node scripts/run-vitest.mjs src/config/config.model-ref-validation.test.ts src/agents/model-catalog.test.ts src/agents/pi-embedded-runner/model.test.ts
• git diff --check
• pnpm docs:list

Real behavior proof

Behavior addressed: Existing configs using available openai-codex GPT-5.1/GPT-5.2/GPT-5.3 refs no longer fail config validation solely because of stale manifest suppressions; removed Spark aliases remain rejected.
Real environment tested: Local source checkout on macOS, targeted Vitest via repo node wrapper.
Exact steps or command run after this patch: node scripts/run-vitest.mjs src/config/config.model-ref-validation.test.ts src/agents/model-catalog.test.ts src/agents/pi-embedded-runner/model.test.ts
Evidence after fix: Config validation accepts openai-codex/gpt-5.2-codex and openai-codex/gpt-5.3-codex fallbacks; catalog/runtime tests keep available Codex rows and resolve openai-codex/gpt-5.3-codex.
Observed result after fix: 5 test files and 227 tests passed.
What was not tested: Live ChatGPT/Codex OAuth request to gpt-5.3-codex and full Docker setup path.

[clawsweeper]

ClawSweeper status: review started.

I am starting a fresh review of this pull request: fix(openai): allow available Codex OAuth models This is item 1/1 in the current shard. Shard 0/1.

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