feat: use structuredContent with outputSchema in example servers (#220)

* build app-with-deps

* make registerAppTool more interchangeable w/ server.registerTool

* feat: use structuredContent in all example servers

All servers now return structuredContent alongside JSON text content.
All mcp-apps now read structuredContent directly (no JSON.parse fallback).

Updated servers:
- basic-server-vanillajs
- budget-allocator-server
- cohort-heatmap-server
- customer-segmentation-server
- integration-server
- scenario-modeler-server
- system-monitor-server
- threejs-server
- video-resource-server
- wiki-explorer-server

* feat: add outputSchema to all example servers

Define output schemas for structuredContent validation:
- basic-server-vanillajs: { time: string }
- budget-allocator-server: BudgetDataResponseSchema
- cohort-heatmap-server: CohortDataSchema
- customer-segmentation-server: customers/segments schema
- integration-server: { time: string }
- scenario-modeler-server: templates/defaultInputs schema
- system-monitor-server: SystemStatsSchema
- threejs-server: { code, height }
- video-resource-server: { videoUri, description }
- wiki-explorer-server: { page, links, error }

* prettier:fix

* make registerAppTool more interchangeable w/ server.registerTool

* feat: use structuredContent in all example servers

All servers now return structuredContent alongside JSON text content.
All mcp-apps now read structuredContent directly (no JSON.parse fallback).

Updated servers:
- basic-server-vanillajs
- budget-allocator-server
- cohort-heatmap-server
- customer-segmentation-server
- integration-server
- scenario-modeler-server
- system-monitor-server
- threejs-server
- video-resource-server
- wiki-explorer-server

* feat: add outputSchema to all example servers

Define output schemas for structuredContent validation:
- basic-server-vanillajs: { time: string }
- budget-allocator-server: BudgetDataResponseSchema
- cohort-heatmap-server: CohortDataSchema
- customer-segmentation-server: customers/segments schema
- integration-server: { time: string }
- scenario-modeler-server: templates/defaultInputs schema
- system-monitor-server: SystemStatsSchema
- threejs-server: { code, height }
- video-resource-server: { videoUri, description }
- wiki-explorer-server: { page, links, error }

* prettier:fix

* revert: remove unrelated workflow, version, and arch changes

* chore: update package-lock.json

* refactor(basic-server-vanillajs): address PR review comments

- Simplify server.ts to return plain time string in text content (not JSON),
  matching the quickstart guide pattern
- Add defensive coding in mcp-app.ts with optional chaining and fallback
  to handle potential type mismatches gracefully

* refactor: restore rich text formatting for LLM-readable content

Restore the human-readable text formatting functions that were removed,
providing meaningful summaries in the text content while keeping
structuredContent for programmatic UI consumption:

- budget-allocator-server: formatBudgetSummary with config overview
- cohort-heatmap-server: formatCohortSummary with retention stats
- scenario-modeler-server: formatScenarioSummary with financial metrics

examples/wiki-explorer-server/server.ts

@@ -95,6 +95,19 @@ export function createServer(): McpServer {
           .default("https://en.wikipedia.org/wiki/Model_Context_Protocol")
           .describe("Wikipedia page URL"),
       }),
+      outputSchema: z.object({
+        page: z.object({
+          url: z.string(),
+          title: z.string(),
+        }),
+        links: z.array(
+          z.object({
+            url: z.string(),
+            title: z.string(),
+          }),
+        ),
+        error: z.string().nullable(),
+      }),
       _meta: { [RESOURCE_URI_META_KEY]: resourceUri },
     },
     async ({ url }): Promise<CallToolResult> => {
@@ -121,11 +134,17 @@ export function createServer(): McpServer {
         const links = extractWikiLinks(new URL(url), html);
 
         const result = { page: { url, title }, links, error: null };
-        return { content: [{ type: "text", text: JSON.stringify(result) }] };
+        return {
+          content: [{ type: "text", text: JSON.stringify(result) }],
+          structuredContent: result,
+        };
       } catch (err) {
         const error = err instanceof Error ? err.message : String(err);
         const result = { page: { url, title }, links: [], error };
-        return { content: [{ type: "text", text: JSON.stringify(result) }] };
+        return {
+          content: [{ type: "text", text: JSON.stringify(result) }],
+          structuredContent: result,
+        };
       }
     },
   );