Phase 2: Refactor Sampling/Elicitation cluster to MCP SDK types

Replace ad hoc local types with SDK schema types across the Sampling
and Elicitation group components.

- SamplingRequestPanel: accept `request: CreateMessageRequestParams` +
  `draftResult: CreateMessageResult` instead of 16 flat props; derive
  messages, model preferences, and parameters from the request object;
  drop `tools`/`toolChoice` (not in MCP 2025-11-25 CreateMessageRequest)
- InlineSamplingRequest: accept `request: CreateMessageRequestParams`;
  derive messagePreview and modelHints from the request
- ElicitationFormPanel: accept `request: ElicitRequest['params']` +
  `serverName`; pass requestedSchema directly to SchemaForm
- ElicitationUrlPanel: rename `elicitationId` to `requestId`
- InlineElicitationRequest: accept `request: ElicitRequest['params']`;
  discriminate form vs URL mode on request shape instead of `mode` prop
- PendingClientRequests: unchanged (children-based wrapper)
- Delete local `SamplingTool` type
- Update all stories with real SDK type fixtures

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

clients/web/src/components/groups/ElicitationUrlPanel/ElicitationUrlPanel.stories.tsx

@@ -10,7 +10,7 @@ const meta: Meta<typeof ElicitationUrlPanel> = {
     onOpenInBrowser: fn(),
     onCancel: fn(),
     message: "Please authenticate with the external service.",
-    elicitationId: "elicit-abc-123",
+    requestId: "elicit-abc-123",
   },
 };
 

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

@@ -12,7 +12,7 @@ import {
 export interface ElicitationUrlPanelProps {
   message: string;
   url: string;
-  elicitationId: string;
+  requestId: string;
   isWaiting: boolean;
   onCopyUrl: () => void;
   onOpenInBrowser: () => void;
@@ -39,14 +39,14 @@ const MetaText = Text.withProps({
   c: "dimmed",
 });
 
-function formatElicitationId(id: string): string {
-  return `Elicitation ID: ${id}`;
+function formatRequestId(id: string): string {
+  return `Request ID: ${id}`;
 }
 
 export function ElicitationUrlPanel({
   message,
   url,
-  elicitationId,
+  requestId,
   isWaiting,
   onCopyUrl,
   onOpenInBrowser,
@@ -73,7 +73,7 @@ export function ElicitationUrlPanel({
           <HintText>Waiting for completion...</HintText>
         </Group>
       )}
-      <MetaText>{formatElicitationId(elicitationId)}</MetaText>
+      <MetaText>{formatRequestId(requestId)}</MetaText>
       <Alert color="yellow" title="Warning">
         This will open an external URL. Verify the domain before proceeding.
       </Alert>