fix: surface list-fetch failures instead of swallowing them

A list load that failed — a transport error, or a result the SDK's era
codec rejects as invalid — reported nothing. The connect-time refresh is
fired with no caller to await it (`void this.refresh()`), so its rejection
became an unhandled rejection: the header said "Connected", the panel
rendered an empty list indistinguishable from a server that has none, and
the failed exchange showed in the Protocol panel as a clean success.

Two surfaces now tell the truth:

- ManagedListState records the failure as observable state (`getError` +
  an `errorChange` event) and still re-throws, so App's auth-recovery
  wrapper keeps working. The four `useManaged*` hooks expose it via a
  shared `useManagedListError`, and the Tools/Prompts/Resources sidebars
  render a `ListLoadError` alert with the reason and a Retry.
- A response the client refused is attributed back to its Protocol entry
  (`markResponseRejected` → `responseRejected` → `MessageEntry.clientError`),
  which now renders an Error status and a "Rejected by the Inspector"
  alert rather than the green resultType badge alone. The SDK gives no
  request id with a decode failure, so the id is recovered by correlation;
  see the comment on `markResponseRejected` for why that is exact.

Also stops `listAllTools` from dropping a failing excluded-tools walk on
the floor — it stays non-fatal but is logged.

Closes #1953

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SW1p8E2uiyyLx4RKwrwSrt

core/mcp/state/managedToolsState.ts

@@ -8,17 +8,11 @@ import type { Tool } from "@modelcontextprotocol/client";
 import {
   ManagedListState,
   DEFAULT_LIST_CHANGED_DEBOUNCE_MS,
+  type ManagedListEventMap,
 } from "./managedListState.js";
 
-export interface ManagedToolsStateEventMap {
+export interface ManagedToolsStateEventMap extends ManagedListEventMap {
   toolsChange: Tool[];
-  /**
-   * Fires when the "list changed since last refresh" flag flips. True when a
-   * `tools/list_changed` arrives (auto-refresh off), false once the user
-   * refreshes or the connection drops. Drives the sidebar list-changed
-   * indicator (#1402).
-   */
-  listChangedChange: boolean;
 }
 
 export class ManagedToolsState extends ManagedListState<
@@ -30,6 +24,7 @@ export class ManagedToolsState extends ManagedListState<
     debounceMs = DEFAULT_LIST_CHANGED_DEBOUNCE_MS,
   ) {
     super(client, {
+      listMethod: "tools/list",
       changeEvent: "toolsChange",
       listChangedEvent: "toolsListChanged",
       capabilityKey: "tools",