fix: Add enhanced retry logic for TerminateInstance rate limiting

- Add RateLimitRetryConfig with 8 attempts, longer delays (up to 120s)
- Enhance TerminateInstance to use two-tier retry approach:
  1. First attempt with default retry (3 attempts, 30s max)
  2. If rate limited, retry with extended backoff (8 attempts, 120s max)
- Add explicit "TooManyRequests" and "429" to retryable patterns
- Addresses HTTP 429 errors on OCI Compute Service TerminateInstance API

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: haimari

pkg/providers/oci/client.go

@@ -385,7 +385,8 @@ func (c *Client) TerminateInstance(ctx context.Context, instanceID string) error
 	logger := log.FromContext(ctx)
 	logger.Info("terminating OCI instance", "instanceID", instanceID)
 
-	return WithRetry(ctx, DefaultRetryConfig(), "terminate-instance", func() error {
+	// First attempt with default retry config
+	err := WithRetry(ctx, DefaultRetryConfig(), "terminate-instance", func() error {
 		request := core.TerminateInstanceRequest{
 			InstanceId:         &instanceID,
 			PreserveBootVolume: common.Bool(false),
@@ -398,6 +399,28 @@ func (c *Client) TerminateInstance(ctx context.Context, instanceID string) error
 
 		return nil
 	})
+
+	// If first attempt failed with rate limiting, retry with more aggressive backoff
+	if err != nil && IsRateLimitError(err) {
+		logger.Info("initial terminate attempt hit rate limit, retrying with extended backoff", 
+			"instanceID", instanceID, "error", err)
+			
+		return WithRetry(ctx, RateLimitRetryConfig(), "terminate-instance-rate-limited", func() error {
+			request := core.TerminateInstanceRequest{
+				InstanceId:         &instanceID,
+				PreserveBootVolume: common.Bool(false),
+			}
+
+			_, err := c.computeClient.TerminateInstance(ctx, request)
+			if err != nil {
+				return WrapOCIError(err, "instance")
+			}
+
+			return nil
+		})
+	}
+
+	return err
 }
 
 // GetInstance retrieves instance details

pkg/providers/oci/errors.go

@@ -55,6 +55,16 @@ func DefaultRetryConfig() RetryConfig {
 	}
 }
 
+// RateLimitRetryConfig returns a retry configuration optimized for rate limiting scenarios
+func RateLimitRetryConfig() RetryConfig {
+	return RetryConfig{
+		MaxAttempts:  8,                // More attempts for rate limiting
+		InitialDelay: 2 * time.Second,  // Start with longer delay
+		MaxDelay:     120 * time.Second, // Much longer max delay for severe rate limiting
+		Factor:       2.5,              // More aggressive backoff
+	}
+}
+
 // WithRetry executes a function with exponential backoff retry
 func WithRetry(ctx context.Context, config RetryConfig, operation string, fn func() error) error {
 	logger := log.FromContext(ctx)
@@ -136,8 +146,10 @@ func isRetryableError(err error) bool {
 			"connection refused",
 			"temporary failure",
 			"too many requests",
+			"TooManyRequests",
 			"rate limit",
 			"throttled",
+			"429",
 		}
 
 		for _, pattern := range retryablePatterns {