fix(build): align Rollup native packages with supported platforms (#337)

Fixes #324

## Summary
- declare root Rollup optional dependencies for the repo's current
supported build matrix: macOS x64/arm64, Linux x64/arm64, and Windows
x64
- pin those root platform packages to the same Rollup version already
used by the repo
- keep the existing workflow/manual-install fallback steps in place for
now

## Validation
- regenerated `package-lock.json` with `npm install --package-lock-only
--ignore-scripts`
- verified the root package entry now records the supported platform
packages under `optionalDependencies`
- kept the change scoped to the platforms currently represented in
workflows and `packages/tauri-app/scripts/prebuild.js`

package.json

@@ -30,5 +30,12 @@
   },
   "devDependencies": {
     "baseline-browser-mapping": "^2.9.11"
+  },
+  "optionalDependencies": {
+    "@rollup/rollup-darwin-arm64": "4.52.5",
+    "@rollup/rollup-darwin-x64": "4.52.5",
+    "@rollup/rollup-linux-arm64-gnu": "4.52.5",
+    "@rollup/rollup-linux-x64-gnu": "4.52.5",
+    "@rollup/rollup-win32-x64-msvc": "4.52.5"
   }
 }