chore(test): scope root bun test to bin/script/src

Default `bun test` recurses into every directory and would pick up
`web/e2e/*.spec.ts` once the marketing site lands. Explicitly listing
the existing test roots (matching script/run-ci-tests.ts TEST_ROOTS)
keeps plugin tests isolated from web E2E tests without needing a
`testPathIgnorePatterns` that bunfig.toml does not support yet.

package.json

@@ -34,7 +34,7 @@
     "prepublishOnly": "bun run clean && bun run build",
     "test:model-capabilities": "bun test src/shared/model-capability-aliases.test.ts src/shared/model-capability-guardrails.test.ts src/shared/model-capabilities.test.ts src/cli/doctor/checks/model-resolution.test.ts --bail",
     "typecheck": "tsc --noEmit",
-    "test": "bun test"
+    "test": "bun test bin script src"
   },
   "keywords": [
     "opencode",