feat(file-ops): add debug logging to verify AOT usage

Added FILE_OPS_DEBUG environment variable support to help verify
that AOT artifacts are being used correctly.

Debug output shows:
- Platform detection (e.g., darwin_arm64)
- AOT artifact path resolution
- Whether AOT or fallback WASM is used

Usage:
  FILE_OPS_DEBUG=1 bazel-bin/tools/file_ops_external/file_ops_external config.json

Verified in testing:
- AOT artifacts extracted correctly for all 6 platforms
- Platform detection working (darwin_arm64 detected)
- AOT artifact used by default (not fallback)
- File operations complete successfully with AOT
- Embedded fallback still works when requested

Author: avrabe

tools/file_ops_external/main.go

@@ -45,7 +45,14 @@ func main() {
 	if err == nil {
 		if _, err := os.Stat(aotPath); err == nil {
 			useAOT = true
+			if os.Getenv("FILE_OPS_DEBUG") != "" {
+				log.Printf("DEBUG: Using AOT artifact for platform %s at %s", platformName, aotPath)
+			}
+		} else if os.Getenv("FILE_OPS_DEBUG") != "" {
+			log.Printf("DEBUG: AOT artifact not found at %s: %v", aotPath, err)
 		}
+	} else if os.Getenv("FILE_OPS_DEBUG") != "" {
+		log.Printf("DEBUG: Failed to locate AOT artifact: %v", err)
 	}
 
 	// Build wasmtime command