feat: introduced omptype validation package and migrated workspace dependencies

- Introduce `@oh-my-pi/omptype` as a new ArkType-compatible schema validation package featuring a lazy JIT runtime, JSON Schema emission, and compatibility adapters.
- Replace `arktype` across workspace packages and test utilities with `@oh-my-pi/omptype`.
- Add benchmark suites, tests, and documentation for the new validation engine and adapters.
- Update workspace build, test runner, and release configurations to include the new package.

packages/coding-agent/test/write-xdev-dispatch.test.ts

@@ -2,6 +2,7 @@ import { describe, expect, it } from "bun:test";
 import * as fs from "node:fs/promises";
 import * as os from "node:os";
 import * as path from "node:path";
+import { type } from "@oh-my-pi/omptype";
 import type { AgentTool } from "@oh-my-pi/pi-agent-core";
 import { Settings } from "@oh-my-pi/pi-coding-agent/config/settings";
 import * as themeModule from "@oh-my-pi/pi-coding-agent/modes/theme/theme";
@@ -22,7 +23,6 @@ import {
 	xdevEntries,
 } from "@oh-my-pi/pi-coding-agent/tools/xdev";
 import { removeWithRetries } from "@oh-my-pi/pi-utils";
-import { type } from "arktype";
 
 // xdev mounting is default-on: discoverable tools like ast_edit unmount into
 // xd://, and a plain `write xd://ast_edit` dispatches them. These guard the