UI housekeeping: Update Modal.children from JSX.Element to React.ReactNode, remove empty fragment wrappers (#41394)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **Refactor**
* Simplified modal structures across multiple dialog components for
improved code maintainability.
* Enhanced modal component's flexibility to support broader content
types.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

frontend/components/ActivityDetails/InstallDetails/SoftwareInstallDetailsModal/SoftwareInstallDetailsModal.tsx

@@ -431,16 +431,14 @@ export const SoftwareInstallDetailsModal = ({
       onEnter={onCancel}
       className={baseClass}
     >
-      <>
-        {renderContent()}
-        <ModalButtons
-          deviceAuthToken={deviceAuthToken}
-          status={swInstallResult?.status}
-          hostSoftwareId={hostSoftware?.id}
-          onRetry={onRetry}
-          onCancel={onCancel}
-        />
-      </>
+      {renderContent()}
+      <ModalButtons
+        deviceAuthToken={deviceAuthToken}
+        status={swInstallResult?.status}
+        hostSoftwareId={hostSoftware?.id}
+        onRetry={onRetry}
+        onCancel={onCancel}
+      />
     </Modal>
   );
 };

frontend/components/ActivityDetails/InstallDetails/SoftwareIpaInstallDetailsModal/SoftwareIpaInstallDetailsModal.tsx

@@ -430,16 +430,14 @@ export const SoftwareIpaInstallDetailsModal = ({
       onEnter={onCancel}
       className={baseClass}
     >
-      <>
-        {renderContent()}
-        <ModalButtons
-          deviceAuthToken={deviceAuthToken}
-          hostSoftwareId={hostSoftware?.id}
-          onRetry={onRetry}
-          onCancel={onCancel}
-          displayStatus={displayStatus}
-        />
-      </>
+      {renderContent()}
+      <ModalButtons
+        deviceAuthToken={deviceAuthToken}
+        hostSoftwareId={hostSoftware?.id}
+        onRetry={onRetry}
+        onCancel={onCancel}
+        displayStatus={displayStatus}
+      />
     </Modal>
   );
 };

frontend/components/ActivityDetails/InstallDetails/SoftwareScriptDetailsModal/SoftwareScriptDetailsModal.tsx

@@ -327,16 +327,14 @@ export const SoftwareScriptDetailsModal = ({
       onEnter={onCancel}
       className={baseClass}
     >
-      <>
-        {renderContent()}
-        <ModalButtons
-          deviceAuthToken={deviceAuthToken}
-          installResultStatus={swInstallResult?.status}
-          hostSoftwareId={hostSoftware?.id}
-          onRerun={onRerun}
-          onCancel={onCancel}
-        />
-      </>
+      {renderContent()}
+      <ModalButtons
+        deviceAuthToken={deviceAuthToken}
+        installResultStatus={swInstallResult?.status}
+        hostSoftwareId={hostSoftware?.id}
+        onRerun={onRerun}
+        onCancel={onCancel}
+      />
     </Modal>
   );
 };

frontend/components/ActivityDetails/InstallDetails/SoftwareUninstallDetailsModal/SoftwareUninstallDetailsModal.tsx

@@ -271,16 +271,14 @@ const SoftwareUninstallDetailsModal = ({
       onEnter={onCancel}
       className={baseClass}
     >
-      <>
-        {renderContent()}
-        <ModalButtons
-          uninstallStatus={uninstallStatus}
-          deviceAuthToken={deviceAuthToken}
-          onCancel={onCancel}
-          onRetry={onRetry}
-          hostSoftware={hostSoftware}
-        />
-      </>
+      {renderContent()}
+      <ModalButtons
+        uninstallStatus={uninstallStatus}
+        deviceAuthToken={deviceAuthToken}
+        onCancel={onCancel}
+        onRetry={onRetry}
+        hostSoftware={hostSoftware}
+      />
     </Modal>
   );
 };

frontend/components/ActivityDetails/InstallDetails/VppInstallDetailsModal/VppInstallDetailsModal.tsx

@@ -484,16 +484,14 @@ export const VppInstallDetailsModal = ({
       onEnter={onCancel}
       className={baseClass}
     >
-      <>
-        {renderContent()}
-        <ModalButtons
-          deviceAuthToken={deviceAuthToken}
-          hostSoftwareId={hostSoftware?.id}
-          onRetry={onRetry}
-          onCancel={onCancel}
-          displayStatus={displayStatus}
-        />
-      </>
+      {renderContent()}
+      <ModalButtons
+        deviceAuthToken={deviceAuthToken}
+        hostSoftwareId={hostSoftware?.id}
+        onRetry={onRetry}
+        onCancel={onCancel}
+        displayStatus={displayStatus}
+      />
     </Modal>
   );
 };

frontend/components/Modal/Modal.tsx

@@ -10,7 +10,7 @@ type ModalWidth = "medium" | "large" | "xlarge" | "auto";
 
 export interface IModalProps {
   title: string | JSX.Element;
-  children: JSX.Element;
+  children: React.ReactNode;
   onExit: () => void;
   onEnter?: () => void;
   /**     medium 650px, large 800px, xlarge 850px, auto auto-width