review: harden version read + fix MonitoringScreen docstring

Address PR #1641 review feedback:

- Add readInspectorVersionSafe() (non-throwing) in core/node/version.ts and use
  it in the web backend, so a failure to resolve the root manifest hides the
  (cosmetic) version badge instead of crashing the backend at startup. Covered
  by tests for both the resolved and unresolvable paths.
- Update MonitoringScreen's docstrings: it now wraps every supplied screen in a
  ScreenStage (only the active tab mounts, cross-fading) rather than rendering
  just the active tab's node.

The third fetch-consolidation suggestion (one useInitialConfig instead of three
GET /api/config hooks) is tracked as a follow-up in #1643.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BrihGWcrM9JGRyu41nzZYw

clients/web/src/components/groups/MonitoringScreen/MonitoringScreen.tsx

@@ -6,7 +6,8 @@ import { ScreenStage } from "../../elements/ScreenStage/ScreenStage";
 export interface MonitoringScreenProps {
   /** Available monitor tabs (Logs/Protocol/Network, filtered by capability). */
   tabs: string[];
-  /** Active monitor tab; keys into `screens` to pick what renders below. */
+  /** Active monitor tab; the matching screen is the mounted one below (the rest
+   *  are cross-faded out via `ScreenStage`). */
   value: string;
   onChange: (tab: string) => void;
   /** Search text for the active screen; wired by the caller to its filter state. */
@@ -38,8 +39,9 @@ const ScreenSlot = Stack.withProps({
 
 /**
  * The pinned monitoring column's content (#1616): a `MonitoringControls` tab row
- * over the currently-selected monitor screen. Layout-only — it renders whichever
- * embedded screen node the caller supplies for the active tab.
+ * over the selected monitor screen. Layout-only — it wraps each supplied screen
+ * node in a `ScreenStage`, so switching tabs cross-fades (only the active tab's
+ * screen is mounted) the same way the primary pane does.
  */
 export function MonitoringScreen({
   tabs,