fix(typebox): migrate to v1 with extension compat (#3474)

* fix(typebox): migrate to v1 with extension compat

Replace AJV-based validation with TypeBox-native validation, keep legacy extension imports working (including @sinclair/typebox/compiler), and restore coercion for serialized/plain JSON schemas.

This change closes #3112.

* fix(typebox): use canonical imports and harden coercion

Switch first-party code to canonical typebox imports while retaining legacy extension aliases in the loader.

Remove obsolete runtime codegen guards, expand serialized JSON-schema coercion coverage, and update related tests and fixtures.

Fixes #3112.

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Co-authored-by: Mario Zechner <badlogicgames@gmail.com>

packages/coding-agent/examples/extensions/truncated-tool.ts

@@ -25,10 +25,10 @@ import {
 	withFileMutationQueue,
 } from "@mariozechner/pi-coding-agent";
 import { Text } from "@mariozechner/pi-tui";
-import { Type } from "@sinclair/typebox";
 import { execSync } from "child_process";
 import { tmpdir } from "os";
 import { join } from "path";
+import { Type } from "typebox";
 
 const RgParams = Type.Object({
 	pattern: Type.String({ description: "Search pattern (regex)" }),