Remove tach (#648)

Remove usage of `tach`

For a small/medium codebase like AgentOps, tach is probably overkill:

codebase is relatively small and focused
The module dependencies are straightforward (event → session, etc.)
Small team size means architectural decisions can be enforced through code review
It wasn't providing any meaningful value the way it was configured
Slows down development unnecessarily
Cases where tach is actually helpful is far from our reality. Let me give some examples:

Large enterprise codebases with 100k+ lines of code
Microservices with strict boundaries that must be enforced
Teams of 10+ developers working across multiple modules

Signed-off-by: Teo <teocns@gmail.com>

CONTRIBUTING.md

@@ -108,7 +108,6 @@ We use the following testing packages:
 - `pytest-mock`: Mocking functionality
 - `pyfakefs`: Mock filesystem operations
 - `requests_mock==1.11.0`: Mock HTTP requests
-- `tach~=0.9`: Performance testing and dependency tracking to prevent circular dependencies
 
 ### Using Tox
 
@@ -216,15 +215,6 @@ This will:
    - Sanitize sensitive information
    - Update cassettes when API changes
 
-5. **Performance Testing**:
-   ```python
-   from tach import Tach
-
-   def test_performance():
-       with Tach('operation_name'):
-           perform_operation()
-   ```
-
 ### CI Testing Strategy
 
 We use Jupyter notebooks as integration tests for LLM providers. This approach:

pyproject.toml

@@ -84,11 +84,6 @@ dev = [
     "pdbpp>=0.10.3",
 ]
 
-# CI dependencies
-ci = [
-    "tach~=0.9"         # Task runner for CI/CD pipelines
-]
-
 [project.urls]
 Homepage = "https://github.com/AgentOps-AI/agentops"
 Issues = "https://github.com/AgentOps-AI/agentops/issues"