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/src/edit/hashline/params.ts

@@ -3,7 +3,7 @@
  * deliberately permissive (allows extra keys) so providers can attach extra
  * keys without rejection; only `input` is required.
  */
-import { type } from "arktype";
+import { type } from "@oh-my-pi/omptype";
 
 export const hashlineEditParamsSchema = type({
 	input: "string",