container: Improve usability of web mode, error handling, and CLI commands

Use --network host so that web interfaces (e.g. opencode web) are
accessible from the host. Suppress Python tracebacks when the tool
exits with a non-zero code. Ignore SIGTSTP to prevent Ctrl+Z from
leaving orphaned containers. Rename force-cleanup to purge.

README.md

@@ -63,12 +63,12 @@ agent-container update
 
 This removes all existing containers and rebuilds the image from scratch. Containers are recreated automatically on the next run. The persistent home directory is not affected.
 
-### Force Cleanup
+### Purge
 
 To remove all containers, the image, and the persistent home directory:
 
 ```sh
-agent-container force-cleanup
+agent-container purge
 ```
 
 ## Sharing host config files via hard links

agent-container.py

@@ -3,6 +3,7 @@
 import hashlib
 import logging
 import os
+import signal
 import subprocess
 import sys
 import time
@@ -16,7 +17,7 @@ Usage:
   agent-container opencode [args...]   Run OpenCode in the container
   agent-container claude [args...]     Run Claude Code in the container
   agent-container update               Rebuild image with latest versions
-  agent-container force-cleanup        Remove all containers, image, and data
+  agent-container purge                Remove all containers, image, and data
 """
 
 
@@ -78,8 +79,8 @@ class AgentContainer:
             )
         elif command == "update":
             self.update()
-        elif command == "force-cleanup":
+        elif command == "purge":
-            self.force_cleanup()
+            self.purge()
         else:
             logger.error(f"Unknown command: {command}")
             print(USAGE, file=sys.stderr)
@@ -132,8 +133,10 @@ class AgentContainer:
                 raise RuntimeError("Container failed to start after recreation")
 
         try:
+            signal.signal(signal.SIGTSTP, signal.SIG_IGN)
             self._exec_tool(tool, args, env_vars, extra_env or {})
         finally:
+            signal.signal(signal.SIGTSTP, signal.SIG_DFL)
             self.stop_container()
 
     def _exec_tool(
@@ -151,7 +154,7 @@ class AgentContainer:
         for var, val in extra_env.items():
             env_args += ["-e", f"{var}={val}"]
 
-        subprocess.run(
+        result = subprocess.run(
             [
                 "docker",
                 "exec",
@@ -163,8 +166,9 @@ class AgentContainer:
                 tool,
                 *args,
             ],
-            check=True,
         )
+        if result.returncode != 0:
+            sys.exit(result.returncode)
 
     # =========================
     # Image handling
@@ -213,6 +217,8 @@ class AgentContainer:
                 "create",
                 "--name",
                 self.container_name,
+                "--network",
+                "host",
                 "--user",
                 f"{self.host_uid}:{self.host_gid}",
                 "--volume",
@@ -263,8 +269,8 @@ class AgentContainer:
         self.build_image(no_cache=True)
         logger.info("Update complete. Containers will be recreated on next run.")
 
-    def force_cleanup(self) -> None:
+    def purge(self) -> None:
-        logger.info("Running force cleanup...")
+        logger.info("Purging all containers, image, and data...")
         self._remove_all_containers()
 
         if self.image_exists():