fix(mcp): exclude tests from the tsc build — unblock release publish

publish.yml builds @gitwand/mcp with `tsc` before publishing; tsc compiled
src/__tests__/preview.test.ts, which imports vitest — not a dependency of the
package (it was symlinked locally as a workaround). Under CI's frozen lockfile
the import is unresolvable, so the build (and thus the whole publish job) failed
with TS2307.

- tsconfig: exclude src/__tests__ + *.test.ts from the build (tests should never
  be compiled into dist/ anyway).
- package.json: drop the `test: vitest run` script — it relied on the same
  unavailable vitest under `pnpm -r run test`, breaking ci.yml too.

The preview tests + vitest.config.ts stay in the repo for local runs. Follow-up:
add vitest to packages/mcp devDependencies + refresh pnpm-lock.yaml on a
pnpm-capable host, then re-enable the test script so CI runs them again.

Author: Laurent Guitton

packages/mcp/package.json

@@ -40,8 +40,7 @@
   },
   "scripts": {
     "build": "tsc",
-    "clean": "rm -rf dist",
-    "test": "vitest run"
+    "clean": "rm -rf dist"
   },
   "dependencies": {
     "@gitwand/core": "workspace:*",

packages/mcp/tsconfig.json

@@ -4,5 +4,6 @@
     "outDir": "dist",
     "rootDir": "src"
   },
-  "include": ["src"]
+  "include": ["src"],
+  "exclude": ["src/__tests__", "src/**/*.test.ts"]
 }