refactor: ♻️ simplify FP16 input and remove redundant code

[onuralpszr]

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

🛠️ This PR makes a small internal cleanup in the model-loading code by simplifying how FP16 input detection is named and handled.

📊 Key Changes

• Renamed the internal variable model_input_fp16 to fp16_input in src/model.rs.
• Removed an unnecessary follow-up assignment that copied model_input_fp16 into fp16_input.
• Kept the existing FP16 input detection logic unchanged; only the variable naming and flow were simplified.

🎯 Purpose & Impact

• Improves code readability ✨ by using a clearer, more direct variable name.
• Reduces minor redundancy 🧹, making the code easier to maintain for contributors.
• Has little to no user-facing impact 👤 since behavior stays the same.
• Lowers the chance of confusion for developers working on model input handling, especially around FP16 support 🔍.

[UltralyticsAssistant]

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[UltralyticsAssistant]

🔍 PR Review

_{Made with ❤️ by Ultralytics Actions}

This PR looks clean. The change is a straightforward variable rename plus removal of a redundant reassignment, and the FP16 detection logic appears unchanged.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

📢 Thoughts on this report? Let us know!

[UltralyticsAssistant]

Merged! 🎉 Thanks for the thoughtful cleanup, @onuralpszr.

As Leonardo da Vinci said, “Simplicity is the ultimate sophistication.” This refinement is a great example of that—clearer fp16_input naming, less redundancy, and easier-to-follow model-loading logic, all while keeping behavior unchanged.

Really appreciate the attention to maintainability and developer clarity here. Contributions like this help keep the codebase clean and approachable for everyone.