feat: use elicitInput() for SEP-1034 default validation

Updates client-side test to validate server-side default application
using elicitInput() helper, which applies defaults via validation layer.
This aligns with the TypeScript SDK's SEP-1034 implementation approach.

The test now validates:
- Server uses elicitInput() with schemas containing defaults
- Client returns empty/partial content
- Server automatically applies defaults during validation
- Defaults are correctly merged for all primitive types

Author: felixweinberger

examples/clients/typescript/elicitation-defaults-test.ts

@@ -27,7 +27,9 @@ async function main(): Promise<void> {
         version: '1.0.0'
       },
       {
-        capabilities: {}
+        capabilities: {
+          elicitation: {}
+        }
       }
     );