fix: restructure src layout to proper package directory

Move src/__init__.py, detect.py, diagnose.py, extract_temp.py, utils/
into src/infrared_data/ to fix wheel package structure. Previously the
whl placed files at root instead of infrared_data/ directory, causing
ModuleNotFoundError on install.

Also update pyproject.toml packages.find config to use standard
src-layout discovery.

pyproject.toml

@@ -19,6 +19,10 @@ dependencies = [
 ]
 
 # PyTorch CUDA版本配置
+
+[tool.setuptools.packages]
+find = {where = ["src"]}
+
 [tool.uv]
 # 指定PyTorch使用CUDA索引
 [[tool.uv.index]]