fix: address flaky tests (#3363)

fix: resolve flaky tests and race conditions in test suite

- Fix telemetry/event tests by patching class methods instead of instances
- Use unique temp files/directories to prevent CI race conditions
- Reset singleton state between tests
- Mock embedchain.Client.setup() to prevent JSON corruption
- Rename test files to test_*.py convention
- Move agent tests to tests/agents directory
- Fix repeated tool usage detection
- Remove database-dependent tools causing initialization errors

tests/experimental/evaluation/metrics/test_base_evaluation_metrics.py

@@ -0,0 +1,29 @@
+import pytest
+from unittest.mock import MagicMock
+from crewai.agent import Agent
+from crewai.task import Task
+
+
+class BaseEvaluationMetricsTest:
+    @pytest.fixture
+    def mock_agent(self):
+        agent = MagicMock(spec=Agent)
+        agent.id = "test_agent_id"
+        agent.role = "Test Agent"
+        agent.goal = "Test goal"
+        agent.tools = []
+        return agent
+
+    @pytest.fixture
+    def mock_task(self):
+        task = MagicMock(spec=Task)
+        task.description = "Test task description"
+        task.expected_output = "Test expected output"
+        return task
+
+    @pytest.fixture
+    def execution_trace(self):
+        return {
+            "thinking": ["I need to analyze this data carefully"],
+            "actions": ["Gathered information", "Analyzed data"],
+        }