Fix basicsr Python 3.13 exec()+locals() crash at runtime startup

basicsr's setup.py get_version() does exec(compile(f.read(),...)) then
locals()['__version__'], which is broken on Python 3.13 — exec() no
longer populates the caller's locals() dict.

Fix: clone BasicSR, patch setup.py to use an explicit namespace dict
(_ns={};exec(...,_ns);return _ns['__version__']), then install from
local path. Dependent face-enhancement packages (realesrgan, gfpgan,
facexlib, face-alignment) are installed in a separate step after.

app.py

@@ -32,13 +32,17 @@ _RUNTIME_PKG_MARKER = Path("/tmp/.runtime_pkgs_installed")
 # 1. Packages requiring --no-build-isolation
 #    - hmr2/skel: declare `chumpy @ git+...` direct-ref dep; chumpy's setup.py does
 #      `from pip._internal.req import parse_requirements` which fails in isolated builds.
-#    - basicsr/realesrgan/gfpgan/facexlib/face-alignment: setup.py imports torch to read
-#      __version__, which fails when torch is not yet present in the isolated build env.
 #    Do NOT list chumpy explicitly — hmr2 pulls it as a transitive dep.
+#    NOTE: basicsr/realesrgan/gfpgan/facexlib/face-alignment are NOT listed here —
+#    basicsr's setup.py get_version() uses exec()+locals() which is broken on Python 3.13
+#    (exec() no longer populates caller's locals()). Handled separately below.
 _NO_ISOLATION_PACKAGES = [
     "hmr2 @ git+https://github.com/shubham-goel/4D-Humans.git@efe18deff163b29dff87ddbd575fa29b716a356c",
     "skel @ git+https://github.com/MarilynKeller/SKEL.git@c32cf16581295bff19399379efe5b776d707cd95",
-    "basicsr",
+]
+
+# Face enhancement packages that depend on basicsr
+_FACE_ENHANCE_PACKAGES = [
     "realesrgan",
     "gfpgan",
     "facexlib",
@@ -74,6 +78,44 @@ def _install_runtime_packages():
         [sys.executable, "-m", "pip", "install", "--quiet", "--upgrade",
          "numpy>=2", "moderngl-window>=3.0.0"], check=True,
     )
+    # basicsr Python 3.13 fix: setup.py get_version() uses exec(compile(...))+locals()
+    # which is broken on Python 3.13 — exec() no longer populates the caller's locals().
+    # Fix: clone the repo, patch setup.py to use an explicit namespace dict, then install.
+    _basicsr_src = Path("/tmp/basicsr-build")
+    if not _basicsr_src.exists():
+        subprocess.run(
+            ["git", "clone", "--depth=1",
+             "https://github.com/XPixelGroup/BasicSR.git", str(_basicsr_src)],
+            check=True,
+        )
+    # Patch get_version() in setup.py: replace locals()['__version__'] pattern
+    _basicsr_setup = _basicsr_src / "setup.py"
+    _setup_src = _basicsr_setup.read_text(encoding="utf-8")
+    # The original pattern: exec(compile(f.read(), ...)); return locals()['__version__']
+    # Replace with an explicit namespace so it works on Python 3.13
+    _patched = _setup_src.replace(
+        "exec(compile(f.read(), version_file, 'exec'))\n    return locals()['__version__']",
+        "_ns = {}\n    exec(compile(f.read(), version_file, 'exec'), _ns)\n    return _ns['__version__']",
+    )
+    if _patched == _setup_src:
+        # Fallback: patch any exec()+locals() version-reading pattern more broadly
+        import re as _re
+        _patched = _re.sub(
+            r"exec\(compile\(([^)]+),\s*'exec'\)\)\s*\n(\s*)return locals\(\)\['__version__'\]",
+            r"_ns = {}\n    exec(compile(\1, 'exec'), _ns)\n\2return _ns['__version__']",
+            _setup_src,
+        )
+    _basicsr_setup.write_text(_patched, encoding="utf-8")
+    subprocess.run(
+        [sys.executable, "-m", "pip", "install", "--quiet", "--no-build-isolation",
+         str(_basicsr_src)],
+        check=True,
+    )
+    # Install face enhancement packages that depend on basicsr
+    subprocess.run(
+        [sys.executable, "-m", "pip", "install", "--quiet", "--no-build-isolation"]
+        + _FACE_ENHANCE_PACKAGES, check=True,
+    )
     subprocess.run(
         [sys.executable, "-m", "pip", "install", "--quiet", "--no-deps"]
         + _NO_DEPS_PACKAGES, check=True,