Add client close

[afourney]

Fixes #4821 by adding a close() method to all clients.

Additionally:

• The m1 CLI is updated to close the client before exiting.
• The playwrightcontroller is updated to suppress some other unrelated chatty warnings (e.g,, produced by markitdown when encountering conversions that require external utilities)

[codecov]

Codecov Report

Attention: Patch coverage is 61.90476% with 8 lines in your changes missing coverage. Please review.

Project coverage is 75.57%. Comparing base (dd82883) to head (350f58d).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...ic_memory/utils/chat_completion_client_recorder.py	50.00%	1 Missing ⚠️
.../autogen_ext/models/anthropic/_anthropic_client.py	50.00%	1 Missing ⚠️
...t/src/autogen_ext/models/azure/_azure_ai_client.py	50.00%	1 Missing ⚠️
...autogen_ext/models/cache/_chat_completion_cache.py	50.00%	1 Missing ⚠️
...xt/src/autogen_ext/models/ollama/_ollama_client.py	50.00%	1 Missing ⚠️
...xt/src/autogen_ext/models/openai/_openai_client.py	50.00%	1 Missing ⚠️
...xt/models/replay/_replay_chat_completion_client.py	66.66%	1 Missing ⚠️
...els/semantic_kernel/_sk_chat_completion_adapter.py	50.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5871      +/-   ##
==========================================
- Coverage   75.60%   75.57%   -0.03%     
==========================================
  Files         189      189              
  Lines       12734    12754      +20     
==========================================
+ Hits         9627     9639      +12     
- Misses       3107     3115       +8     

Flag	Coverage Δ
unittests	75.57% <61.90%> (-0.03%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[ekzhu]

Created #5873 to track doc updates