Context-aware network calls

Always propagate context through network calls to ensure proper cancellation, timeout handling, and tracing. For HTTP requests, use http.NewRequestWithContext() instead of http.Post() or http.Get(). For gRPC, ensure context is passed and enriched with necessary metadata.

When adding metadata to context:

• For single values, use metadata.AppendToOutgoingContext(ctx, key, value)
• For multiple values, batch them in a single call: metadata.AppendToOutgoingContext(ctx, k1, v1, k2, v2, ...)

Example of context-aware HTTP client:

// Instead of this:
response, err := http.Post(a.opaEndpoint, "application/json", bytes.NewBuffer(jsonData))

// Do this:
req, err := http.NewRequestWithContext(ctx, "POST", a.opaEndpoint, bytes.NewBuffer(jsonData))
if err != nil {
    return resultDeny, err
}
req.Header.Set("Content-Type", "application/json")
response, err := http.DefaultClient.Do(req)

Example of proper gRPC context metadata:

// Batch metadata in a single call
ctx = metadata.AppendToOutgoingContext(ctx, 
    "temporal-test-name", testName,
    "user-id", userId,
    "request-id", requestId)

Context propagation ensures that cancellation signals are properly passed throughout the system, preventing resource leaks and allowing proper tracing of distributed operations.