refactor(scripts): restructure workspace scripts into check:* / test:* families

Replace the opaque `vp check` bundling and the ad-hoc `ready` chain (which
shelled out via `cd ... && pnpm ...`) with explicit, composable named scripts.

Root delegates; category splits live in the package that owns them:

  root: check:fmt / check:lint / check:fixtures / test / build / ready
  runtime-tests: test = test:integration + test:pty; check:fixtures

`ready` now composes the named scripts in dependency order (fmt, lint, build,
fixtures, test) — build runs before check:fixtures and test:pty, which need
the built dist. Drop the broken root `dev` (referenced a non-existent website
package) and the redundant per-package `check` scripts (fmt/lint already run
workspace-wide from root). Renames: pty-test -> test:pty, typecheck:fixtures
-> check:fixtures.

packages/runtime-tests/package.json

@@ -4,10 +4,10 @@
   "private": true,
   "type": "module",
   "scripts": {
-    "test": "vp test",
-    "pty-test": "vp test run --config vitest.pty.config.ts --passWithNoTests",
-    "typecheck:fixtures": "tsc -p integration/pty/fixtures/tsconfig.json --noEmit",
-    "check": "vp check"
+    "test": "vp run test:integration && vp run test:pty",
+    "test:integration": "vp test",
+    "test:pty": "vp test run --config vitest.pty.config.ts --passWithNoTests",
+    "check:fixtures": "tsc -p integration/pty/fixtures/tsconfig.json --noEmit"
   },
   "devDependencies": {
     "@types/node": "^25.9.1",