Sidebar metadata + tagged reload isolation (#16)

* Sidebar primitives + tagged dev isolation

* Allow wider sidebar resize

* Fix tagged socket selection + panel id errors

* Fix progress label quoting + bundle suffix sanitize

* Skip ctrl-enter keybind test when keystrokes blocked

* Fix shell nc hang + prune stale per-surface sidebar metadata

tests/test_cpu_usage.py

@@ -19,9 +19,15 @@ import subprocess
 import sys
 import time
 import re
+import os
 from pathlib import Path
 from typing import List, Optional
 
+# Allow importing tests/cmux.py when running from repo root.
+sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
+
+from cmux import cmux
+
 
 # Maximum acceptable CPU usage during idle (percentage)
 MAX_IDLE_CPU_PERCENT = 15.0
@@ -45,6 +51,31 @@ SUSPICIOUS_PATTERNS = [
 
 def get_cmuxterm_pid() -> Optional[int]:
     """Get the PID of the running cmuxterm process."""
+    socket_path = os.environ.get("CMUX_SOCKET_PATH")
+    if not socket_path:
+        try:
+            socket_path = cmux().socket_path
+        except Exception:
+            socket_path = None
+
+    if socket_path and os.path.exists(socket_path):
+        result = subprocess.run(
+            ["lsof", "-t", socket_path],
+            capture_output=True,
+            text=True,
+        )
+        if result.returncode == 0:
+            for line in result.stdout.strip().split("\n"):
+                line = line.strip()
+                if not line:
+                    continue
+                try:
+                    pid = int(line)
+                except ValueError:
+                    continue
+                if pid != os.getpid():
+                    return pid
+
     result = subprocess.run(
         ["pgrep", "-f", r"cmuxterm\.app/Contents/MacOS/cmuxterm$"],
         capture_output=True,
@@ -156,7 +187,7 @@ def main():
                 print(f"  - {issue}")
 
         # Save sample for debugging
-        sample_file = Path("/tmp/cmuxterm_cpu_test_sample.txt")
+        sample_file = Path(f"/tmp/cmuxterm_cpu_test_sample_{pid}.txt")
         sample_file.write_text(sample_output)
         print(f"\nFull sample saved to: {sample_file}")