Replace Zod with TypeBox for schema validation

- Switch from Zod to TypeBox for tool parameter schemas
- TypeBox schemas can be serialized/deserialized as JSON
- Use AJV for runtime validation instead of Zod's parse
- Add StringEnum helper for Google API compatibility (avoids anyOf/const patterns)
- Export Type and Static from main package for convenience
- Update all tests and documentation to reflect TypeBox usage

packages/ai/src/agent/tools/calculate.ts

@@ -1,4 +1,4 @@
-import { z } from "zod";
+import { type Static, Type } from "@sinclair/typebox";
 import type { AgentTool } from "../../agent";
 
 export interface CalculateResult {
@@ -15,10 +15,12 @@ export function calculate(expression: string): CalculateResult {
 	}
 }
 
-const calculateSchema = z.object({
-	expression: z.string().describe("The mathematical expression to evaluate"),
+const calculateSchema = Type.Object({
+	expression: Type.String({ description: "The mathematical expression to evaluate" }),
 });
 
+type CalculateParams = Static<typeof calculateSchema>;
+
 export const calculateTool: AgentTool<typeof calculateSchema, undefined> = {
 	label: "Calculator",
 	name: "calculate",