Add OpenAI-compatible TTS

[taowang1993]

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1. Is this request related to a challenge you're experiencing? Tell me about your story.

Please consider adding OpenAI-compatible TTS.

2. Additional context or comments

No response

3. Can you help us with this feature?

• [ ] I am interested in contributing to this feature.

[dosubot[bot]]

Hi, @taowang1993. I'm Dosu, and I'm helping the Dify team manage their backlog. I'm marking this issue as stale.

Issue Summary:

• You requested the integration of OpenAI-compatible text-to-speech functionality.
• A screenshot was provided for reference, but no further details were included.
• There has been no additional activity or comments on this issue.

Next Steps:

• Please let me know if this issue is still relevant to the latest version of the Dify repository by commenting here.
• If there is no further activity, this issue will be automatically closed in 15 days.

Thank you for your understanding and contribution!