Pnnx numpy file input

[AtomAlpaca]

主要改动：

• 为 pnnx 添加 input 和 input2 参数，支持从 npy 文件获取输入 tensor 的 shape 和内容

[github-actions]

The binary size change of libncnn.so (bytes)

architecture	base size	pr size	difference
x86_64	15124728	15124728	0 😘
armhf	6155744	6155744	0 😘
aarch64	9453192	9453192	0 😘

[nihui]

感谢你的工作，请将你在实现中的笔记和心得，遇到的困难和解决方法等，记录成文章，发表在discussion分区，这将作为知识总结 https://github.com/Tencent/ncnn/discussions

Thank you for your work. Please record your notes and experience in the implementation, difficulties encountered and solutions, etc. into an article and publish it in the discussion section. This will serve as a knowledge summary. https://github.com/Tencent/ncnn/discussions

[tencent-adm]

Thank you for your submission, we really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
1 out of 2 committers have signed the CLA.

✅ AtomAlpaca
❌ nihui
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[Copilot]

Pull Request Overview

This PR adds support for using numpy files as input data sources for the pnnx tool, enabling users to specify input tensor shapes and contents directly from .npy files instead of manually defining shapes.

• Adds input and input2 parameters to accept comma-separated numpy file paths
• Implements numpy file parsing functionality with support for different endianness, data types, and array ordering
• Updates the torchscript loading process to use actual tensor data from numpy files when available

Reviewed Changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 16 comments.

Show a summary per file

File	Description
tools/pnnx/src/utils.h	Adds function declarations for numpy file parsing utilities
tools/pnnx/src/utils.cpp	Implements numpy file parsing with endianness, fortran order, and data type handling
tools/pnnx/src/main.cpp	Adds command-line parameter parsing for input and input2 options
tools/pnnx/src/load_torchscript.h	Updates function signature to accept input content vectors
tools/pnnx/src/load_torchscript.cpp	Modifies tensor creation to use numpy data when available
tools/pnnx/tests/numpy/*.py	Test files demonstrating numpy input functionality
tools/pnnx/tests/numpy/CMakeLists.txt	Test configuration for numpy input tests

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