Restore install.py for omnivoice --no-deps only

requirements.txt cannot install omnivoice (it would pull in torch==2.8.*
and break ComfyUI). install.py now does exactly one thing: install
omnivoice --no-deps, skipped if already present. All other deps remain
in requirements.txt for ComfyUI Manager to handle normally.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

install.py

@@ -0,0 +1,21 @@
+"""
+ComfyUI Manager calls this file before installing requirements.txt.
+
+omnivoice cannot be listed in requirements.txt because its default install
+pins torch==2.8.* from a CUDA 12.8 index, which would overwrite ComfyUI's
+torch build. We install it here with --no-deps to skip that pin.
+All other dependencies are declared normally in requirements.txt.
+"""
+import subprocess
+import sys
+
+
+def _installed(package):
+    import importlib.util
+    return importlib.util.find_spec(package) is not None
+
+
+if not _installed("omnivoice"):
+    subprocess.check_call([
+        sys.executable, "-m", "pip", "install", "omnivoice", "--no-deps"
+    ])