feat(tool-rails): add support for tool output rails and validation

[Pouyanpi]

Introduce tool output/input rails configuration and Colang flows for tool call validation and parameter security checks. Add support for BotToolCall event emission in passthrough mode, enabling tool call guardrails before execution.

must be merged after #1370 #1369 #1366

[Copilot]

Pull Request Overview

This PR introduces support for tool output/input rails configuration and Colang flows for tool call validation and parameter security checks. It also enables BotToolCall event emission in passthrough mode, allowing tool call guardrails to be executed before tool execution.

• Adds ToolOutputRails and ToolInputRails configuration classes with flows support
• Implements tool output rails flows execution in the Colang runtime
• Creates BotToolCall events when tool_calls are detected in passthrough mode, bypassing output rails

Reviewed Changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
tests/test_tool_output_rails.py	Test suite for tool output rails functionality with validation flows
tests/test_tool_calls_event_extraction.py	Tests for tool_calls preservation and event-based extraction
tests/test_tool_calling_passthrough_only.py	Tests verifying tool calling only works in passthrough mode
tests/test_tool_calling_passthrough_integration.py	Integration tests for passthrough mode tool calling
tests/test_output_rails_tool_calls.py	Tests verifying output rails are bypassed for tool calls
tests/test_bot_tool_call_events.py	Tests for BotToolCall event handling
tests/runnable_rails/test_tool_calling.py	RunnableRails integration tests for tool calling
nemoguardrails/rails/llm/options.py	Added tool_output and tool_input options to GenerationRailsOptions
nemoguardrails/rails/llm/llmrails.py	Modified to use extract_tool_calls_from_events instead of contextvar
nemoguardrails/rails/llm/llm_flows.co	Added tool output rails flow processing
nemoguardrails/rails/llm/config.py	Added ToolOutputRails and ToolInputRails configuration classes
nemoguardrails/actions/llm/utils.py	Added extract_tool_calls_from_events function
nemoguardrails/actions/llm/generation.py	Modified to emit BotToolCall events in passthrough mode

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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