CI: add trainer PyInstaller build script

Author: Abe404

trainer/src/build/run_pyinstaller_trainer.py

@@ -0,0 +1,35 @@
+from pathlib import Path
+import PyInstaller.__main__
+
+HERE = Path(__file__).resolve().parent          # trainer/src/build
+SRC  = HERE.parent                               # trainer/src
+ENTRY = SRC / "main.py"
+
+DIST = SRC / "dist"
+WORK = SRC / "build" / "_pyi_work"
+
+PyInstaller.__main__.run([
+    "--noconfirm",
+    "--clean",
+    "--name", "RootPainterTrainer",
+    "--console",
+
+    # CRITICAL: make trainer/src importable during analysis (so 'trainer.py' is found)
+    "--paths", str(SRC),
+
+    # Ensure local module is bundled
+    "--hidden-import", "trainer",
+
+    # Torch bits
+    "--hidden-import", "torch",
+    "--hidden-import", "torchvision",
+    "--hidden-import", "torchvision.ops",
+    "--hidden-import", "torchvision.io",
+    "--hidden-import", "torchvision.transforms",
+
+    "--distpath", str(DIST),
+    "--workpath", str(WORK),
+    str(ENTRY),
+])
+
+print("Built:", DIST / "RootPainterTrainer")