openai[minor],docs[minor]: Add parallel tool calls call option and docs #13539

Job	Run time
Check linting	5m 30s
test-exports / exports-esbuild	5m 10s
test-exports / exports-esm	4m 58s
test-exports / exports-cf	4m 41s
test-exports / exports-cjs	4m 44s
test-exports / exports-vercel	5m 58s
test-exports / exports-tsc	4m 42s
test-exports / exports-vite	4m 38s
	40m 21s

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