CLI tool commands hang after displaying output

[divideby0]

Bug Description

CLI commands like basic-memory tool --help and basic-memory status hang indefinitely after displaying output, requiring Ctrl+C to exit.

Reproduction Steps

1. Run uvx basic-memory tool --help
2. Observe: help text displays but process never exits
3. Must Ctrl+C to terminate

Also affects:

• basic-memory tool write-note --help
• basic-memory tool read-note --help
• basic-memory tool search-notes --help
• basic-memory status

Expected Behavior

Command should exit with code 0 after displaying output.

Root Cause

ensure_initialization() and CLI commands create database connections via asyncio.run() that are never cleaned up. The global database engine holds async connections that prevent the process from exiting.

Environment

• basic-memory version: 0.16.x
• Python: 3.12+
• Platform: macOS/Linux

[divideby0]

this one might be a bit of a blocker for some as even basic-memory project add... hangs. i noticed there were some ci failures on my pull request but they seem to be unrelated to the changes:

$ uvx basic-memory@latest project add taskmaster-merge ./context/memory
Installed 105 packages in 407ms

2025-12-20 15:18:39.836 | DEBUG    | basic_memory.api.template_loader:__init__:235 - Initialized template loader with directory: /Users/myuser/.cache/uv/archive-v0/q0WNp3Nb94j1OvizJA01-/lib/python3.12/site-packages/basic_memory/templates
Project 'taskmaster-merge' added successfully

# After manually hitting Ctrl+C

^CException ignored in: <module 'threading' from '/Users/myuser/.local/share/uv/python/cpython-3.12.7-macos-aarch64-none/lib/python3.12/threading.py'>
Traceback (most recent call last):
  File "/Users/myuser/.local/share/uv/python/cpython-3.12.7-macos-aarch64-none/lib/python3.12/threading.py", line 1624, in _shutdown
    lock.acquire()
KeyboardInterrupt: 

[phernandez]

fixed with #471