fix: free meta memory in clip model loading

[yushihang]

Fix Memory Leak in clip.cpp

Changes

• Added ggml_free(meta); in all error handling paths

Testing

• Local CI tests passed
• Verified with llama-perplexity that the changes do not affect model performance
• Verified with llama-bench that the changes do not affect runtime performance
• Tested on:
  • macOS Ventura 13.x
  • Compiler: Apple clang version 14.0.3

Additional Notes

• This is a pure memory management fix without any functional changes
• Changes follow the project's coding guidelines

[yushihang]

I've created separate PRs for each potential issue as I'm not entirely confident about the project's preferences for bundling changes.
While this might create more PRs to review, it allows for more focused discussions and easier rollbacks if needed.
I appreciate your patience in reviewing these atomic changes.