feat: add indictor for tool failure to FunctionExecutionResult

[wistuba]

Why are these changes needed?

Some LLMs recieve an explicit signal about tool use failures. This change will allow

Related issue number

Closes #5273

Checks

• I've included any doc changes needed for https://microsoft.github.io/autogen/. See https://microsoft.github.io/autogen/docs/Contribute#documentation to build and test documentation locally.
• I've added tests (if relevant) corresponding to the changes introduced in this PR.
• I've made sure all auto checks have passed.

We probably want to add some additional testing. I need some advice where to add it.

[wistuba]

@microsoft-github-policy-service agree company="Amazon"

[wistuba]

@microsoft-github-policy-service agree company="Amazon"

[ekzhu]

You can run uv sync --all-extras in the 'python' directory to sync your local environment. There is no dependency change so there shouldn't be update to the uv.lock file

[wistuba]

You can run uv sync --all-extras in the 'python' directory to sync your local environment. There is no dependency change so there shouldn't be update to the uv.lock file

I did that. Doesn't help. I manually reverted it, but the uv sync keeps reverting it. With main uv lock, I keep seeing issues with pyright when running poe check. It requires me to manually install pyright which may cause this problem:

RuntimeError: nodeenv failed; for more reliable node.js binaries try `pip install pyright[nodejs]`
Error: Sequence aborted after failed subtask 'pyright'

[ekzhu]

Could you try to purge your local virtualenv completely and recreate on again. Also make sure your uv installation is up-to-date.

git clone https://github.com/microsoft/autogen
cd autogen/python
uv venv --python=3.12
source .venv/bin/activate
uv sync --all-extras

I just ran the CI tests and it works. So likely your local environment setup has some issue.

[codecov]

Codecov Report

Attention: Patch coverage is 70.00000% with 6 lines in your changes missing coverage. Please review.

Project coverage is 78.32%. Comparing base (b8c5e49) to head (a18e154).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...togen_ext/agents/openai/_openai_assistant_agent.py	73.33%	4 Missing ⚠️
...t/src/autogen_agentchat/agents/_assistant_agent.py	50.00%	1 Missing ⚠️
...n-core/src/autogen_core/tool_agent/_caller_loop.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5428      +/-   ##
==========================================
- Coverage   78.32%   78.32%   -0.01%     
==========================================
  Files         165      165              
  Lines        9800     9803       +3     
==========================================
+ Hits         7676     7678       +2     
- Misses       2124     2125       +1     

Flag	Coverage Δ
unittests	78.32% <70.00%> (-0.01%)	⬇️

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.

[ekzhu]

Thanks! For now we don't really have a sample showing this. I believe with Anthropic model client, we can utlize the error field to indicate error, as described there: https://docs.anthropic.com/en/docs/build-with-claude/tool-use#troubleshooting-errors.

#5205