refactor: re-export types from sdk.types.ts instead of using Infer<>

Replace ~130 Infer<typeof Schema> type exports with re-exports from
generated sdk.types.ts. This removes duplication and uses cleaner types
without index signatures.

Only 7 SDK-specific types still use Infer<>:
- JSONRPCResponse (local union of result/error)
- Progress (SDK-specific schema)
- TaskCreationParams (SDK-specific)
- CompatibilityCallToolResult (backwards-compat helper)
- SamplingContent (SDK discriminated union)
- CreateMessageResultWithTools (SDK extension)
- ElicitationCompleteNotificationParams (SDK extension)

Also fixes:
- Add `as const` assertions for ElicitResult action literals
- Handle SamplingMessage.content being array or single block
- Cast TaskStatusNotification through unknown for generic constraints

Note: test/client/index.test.ts has type errors exposed by stricter types.
The tests use incorrect ClientCapabilities structures that were previously
allowed by index signatures.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: ochafik

src/examples/client/simpleStreamableHttp.ts

@@ -381,7 +381,7 @@ async function connect(url?: string): Promise<void> {
                 }
 
                 if (inputCancelled) {
-                    return { action: 'cancel' };
+                    return { action: 'cancel' as const };
                 }
 
                 // If we didn't complete all fields due to an error, try again
@@ -394,7 +394,7 @@ async function connect(url?: string): Promise<void> {
                         continue;
                     } else {
                         console.log('Maximum attempts reached. Declining request.');
-                        return { action: 'decline' };
+                        return { action: 'decline' as const };
                     }
                 }
 
@@ -412,7 +412,7 @@ async function connect(url?: string): Promise<void> {
                         continue;
                     } else {
                         console.log('Maximum attempts reached. Declining request.');
-                        return { action: 'decline' };
+                        return { action: 'decline' as const };
                     }
                 }
 
@@ -428,23 +428,23 @@ async function connect(url?: string): Promise<void> {
 
                 if (confirmAnswer === 'yes' || confirmAnswer === 'y') {
                     return {
-                        action: 'accept',
-                        content
+                        action: 'accept' as const,
+                        content: content as { [key: string]: string | number | boolean | string[] }
                     };
                 } else if (confirmAnswer === 'cancel' || confirmAnswer === 'c') {
-                    return { action: 'cancel' };
+                    return { action: 'cancel' as const };
                 } else if (confirmAnswer === 'no' || confirmAnswer === 'n') {
                     if (attempts < maxAttempts) {
                         console.log('Please re-enter the information...');
                         continue;
                     } else {
-                        return { action: 'decline' };
+                        return { action: 'decline' as const };
                     }
                 }
             }
 
             console.log('Maximum attempts reached. Declining request.');
-            return { action: 'decline' };
+            return { action: 'decline' as const };
         });
 
         transport = new StreamableHTTPClientTransport(new URL(serverUrl), {

src/examples/client/simpleTaskInteractiveClient.ts

@@ -14,6 +14,7 @@ import {
     CallToolResultSchema,
     TextContent,
     ElicitRequestSchema,
+    ElicitResult,
     CreateMessageRequestSchema,
     CreateMessageRequest,
     CreateMessageResult,
@@ -44,15 +45,15 @@ async function elicitationCallback(params: {
     mode?: string;
     message: string;
     requestedSchema?: object;
-}): Promise<{ action: string; content?: Record<string, unknown> }> {
+}): Promise<ElicitResult> {
     console.log(`\n[Elicitation] Server asks: ${params.message}`);
 
     // Simple terminal prompt for y/n
     const response = await question('Your response (y/n): ');
     const confirmed = ['y', 'yes', 'true', '1'].includes(response.toLowerCase());
 
     console.log(`[Elicitation] Responding with: confirm=${confirmed}`);
-    return { action: 'accept', content: { confirm: confirmed } };
+    return { action: 'accept' as const, content: { confirm: confirmed } };
 }
 
 async function samplingCallback(params: CreateMessageRequest['params']): Promise<CreateMessageResult> {

src/examples/server/toolWithSampleServer.ts

@@ -33,12 +33,13 @@ mcpServer.registerTool(
             maxTokens: 500
         });
 
-        // Since we're not passing tools param to createMessage, response.content is single content
+        // Extract text from response content (could be single block or array)
+        const contentBlock = Array.isArray(response.content) ? response.content[0] : response.content;
         return {
             content: [
                 {
                     type: 'text',
-                    text: response.content.type === 'text' ? response.content.text : 'Unable to generate summary'
+                    text: contentBlock?.type === 'text' ? contentBlock.text : 'Unable to generate summary'
                 }
             ]
         };

src/shared/protocol.ts

@@ -1584,7 +1584,7 @@ export abstract class Protocol<SendRequestT extends RequestBase, SendNotificatio
                         method: 'notifications/tasks/status',
                         params: task
                     });
-                    await this.notification(notification as SendNotificationT);
+                    await this.notification(notification as unknown as SendNotificationT);
 
                     if (isTerminal(task.status)) {
                         this._cleanupTaskProgressHandler(taskId);
@@ -1619,7 +1619,7 @@ export abstract class Protocol<SendRequestT extends RequestBase, SendNotificatio
                         method: 'notifications/tasks/status',
                         params: updatedTask
                     });
-                    await this.notification(notification as SendNotificationT);
+                    await this.notification(notification as unknown as SendNotificationT);
 
                     if (isTerminal(updatedTask.status)) {
                         this._cleanupTaskProgressHandler(taskId);