chore: add breaking change detector #4

	name: Breaking Change Detector

	on:
	pull_request:
	branches:
	- main
	paths:
	- 'src/**'

	jobs:
	check-api:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout code
	uses: actions/checkout@v4
	with:
	fetch-depth: 0

	- name: Set up Python
	uses: actions/setup-python@v5
	with:
	python-version: '3.10'

	- name: Install dependencies
	uses: astral-sh/setup-uv@v5
	with:
	version: "latest"

	- name: Install project
	run: \|
	uv sync --extra test
	uv pip install griffe

	- name: Run Breaking Change Detection
	run: \|
	uv run python - <<EOF
	import sys
	import griffe
	from griffe import find_breaking_changes, load, load_git

	try:
	# 1. Force static analysis (allow_inspection=False) to avoid sys.modules caching issues
	print("Loading new API...")
	new_api = load("google.adk", search_paths=["src"], allow_inspection=False)

	print("Loading old API...")
	old_api = load_git("google.adk", ref="main", search_paths=["src"], allow_inspection=False)

	# Debug: Verify we are comparing different files
	print(f"DEBUG: New API path: {new_api.filepath}")
	print(f"DEBUG: Old API path: {old_api.filepath}")

	print("Comparing...")
	breakages = list(find_breaking_changes(old_api, new_api))

	if breakages:
	print(f"::error::Found {len(breakages)} breaking changes!")
	for breakage in breakages:
	print(breakage.explain())
	sys.exit(1)

	print("Success: No breaking changes detected.")

	except Exception as e:
	print(f"::error::Breaking change detection failed: {e}")
	sys.exit(1)
	EOF

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