Fix: Kill the server with one keyboard interrupt (#94)

* Initial plan

* Handle KeyboardInterrupt in run_app to allow single Ctrl+C shutdown

Co-authored-by: lstein <111189+lstein@users.noreply.github.com>

* Force os._exit(0) on KeyboardInterrupt to avoid hanging on background threads

Co-authored-by: lstein <111189+lstein@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: lstein <111189+lstein@users.noreply.github.com>

Author: Copilot

invokeai/app/run_app.py

@@ -9,6 +9,8 @@ def get_app():
 
 def run_app() -> None:
     """The main entrypoint for the app."""
+    import os
+
     from invokeai.frontend.cli.arg_parser import InvokeAIArgs
 
     # Parse the CLI arguments before doing anything else, which ensures CLI args correctly override settings from other
@@ -100,4 +102,9 @@ def run_app() -> None:
     for hdlr in logger.handlers:
         uvicorn_logger.addHandler(hdlr)
 
-    loop.run_until_complete(server.serve())
+    try:
+        loop.run_until_complete(server.serve())
+    except KeyboardInterrupt:
+        logger.info("InvokeAI shutting down...")
+        # Force exit to avoid hanging on non-daemon background threads (e.g. model install service).
+        os._exit(0)