chore(oss): audit the server package and resync the SDK mirrors

Split the 657-line operation service into eor, submit, and verify
modules, add the AGENT_REVOKED and KEY_RETIRED codes the Backend already
emits, and condense every multi-line comment. Mirror Node, Python, and
Go at 2.1.0 with the deep-health 503, non-idempotent retry, rotation
grace, and path-encoding fixes. Document which routes and response
fields the self-hosted server does not provide.

Claude-Session: https://claude.ai/code/session_01Agoc9bRVE9KL7mmWtey9Vq

sdks/go/cmd/elydora/main_test.go

@@ -5,6 +5,8 @@ import (
 	"path/filepath"
 	"strings"
 	"testing"
+
+	"github.com/Elydora-Infrastructure/Elydora-Go-SDK/v2/cmd/elydora/plugins"
 )
 
 func setMainTestHome(t *testing.T) string {
@@ -17,9 +19,9 @@ func setMainTestHome(t *testing.T) string {
 
 func TestGuardScriptPathRejectsUnsafeAgentID(t *testing.T) {
 	setMainTestHome(t)
-	_, err := guardScriptPathForAgent("../escape")
+	_, err := plugins.ResolveAgentRuntimeDirectory("../escape")
 	if err == nil || !strings.Contains(err.Error(), "invalid agent ID") {
-		t.Fatalf("guardScriptPathForAgent() error = %v", err)
+		t.Fatalf("ResolveAgentRuntimeDirectory() error = %v", err)
 	}
 }