feat: restore AgentOps documentation and integration

- Add AgentOps optional dependency to pyproject.toml
- Implement AgentOpsListener with event handling for crew kickoff, tool usage, and task evaluation
- Add comprehensive AgentOps documentation in English, Portuguese, and Korean
- Update docs.json navigation to include AgentOps in observability sections
- Add agentops.log to .gitignore
- Include comprehensive tests for AgentOps integration with mocking
- Ensure graceful handling when AgentOps package is not installed

Addresses issue #3348 by restoring AgentOps integration removed in PR #3334

Co-Authored-By: João <joao@crewai.com>

docs/docs.json

@@ -226,6 +226,7 @@
                 "group": "Observability",
                 "pages": [
                   "en/observability/overview",
+                  "en/observability/agentops",
                   "en/observability/arize-phoenix",
                   "en/observability/langdb",
                   "en/observability/langfuse",
@@ -565,6 +566,7 @@
                 "group": "Observabilidade",
                 "pages": [
                   "pt-BR/observability/overview",
+                  "pt-BR/observability/agentops",
                   "pt-BR/observability/arize-phoenix",
                   "pt-BR/observability/langdb",
                   "pt-BR/observability/langfuse",
@@ -912,6 +914,7 @@
                 "group": "Observability",
                 "pages": [
                   "ko/observability/overview",
+                  "ko/observability/agentops",
                   "ko/observability/arize-phoenix",
                   "ko/observability/langdb",
                   "ko/observability/langfuse",