fix: repair npm install and the rollup build

Three independent breakages, all present on main before this branch:

1. `npm ci` always exited non-zero. The root package.json carried
   "install": "node-gyp-build", but binding.gyp lives in native/, so the
   script ran in a directory with nothing to build:

     gyp: binding.gyp not found (cwd: <repo root>)

   native/package.json already declares that same install script in the
   right place, alongside its binding.gyp and "gypfile": true, so the
   root copy was a duplicate in the wrong package. Removing it also
   clears the now-inaccurate hasInstallScript flag from the lockfile.
   `npm ci` exits 0 again; the addon still builds from native/.

2. `npm run build` failed at the first step. @rollup/plugin-typescript
   requires tslib as a peer, and nothing depended on it directly — it was
   only present transitively as an optional dev dep, so a clean install
   could omit it entirely. Declared explicitly.

3. rollup.config.js used ESM syntax while package.json has no
   "type": "module", so Node parsed it as CommonJS and threw
   "Cannot use import statement outside a module". Node 24 recovers by
   reparsing (with a warning); Node 18 fails outright. Renamed to
   rollup.config.mjs, which is unambiguous on both. Setting
   "type": "module" instead would have broken jest.config.js, which is
   CommonJS.

Verified on Node 18.19.1 and Node 24.18.0: npm ci exits 0, npm run build
produces all three bundles plus declarations, and 76/76 tests pass.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

package-lock.json

@@ -7,7 +7,6 @@
         "": {
             "name": "nomyo-js",
             "version": "0.1.0",
-            "hasInstallScript": true,
             "license": "Apache-2.0",
             "devDependencies": {
                 "@rollup/plugin-commonjs": "^29.0.0",
@@ -22,6 +21,7 @@
                 "node-gyp-build": "^4.8.0",
                 "rollup": "^4.0.0",
                 "ts-jest": "^29.4.6",
+                "tslib": "^2.8.1",
                 "typescript": "^6.0.0"
             },
             "engines": {
@@ -5975,7 +5975,7 @@
             "resolved": "https://registry.npmjs.org/tslib/-/tslib-2.8.1.tgz",
             "integrity": "sha512-oJFu94HQb+KVduSUQL7wnpmqnfmLsOA/nAh6b6EH0wCEoK0/mPeXU6c3wKDV83MkOuHPRHtSXKKU99IBazS/2w==",
             "dev": true,
-            "optional": true
+            "license": "0BSD"
         },
         "node_modules/type-detect": {
             "version": "4.0.8",
@@ -10642,8 +10642,7 @@
             "version": "2.8.1",
             "resolved": "https://registry.npmjs.org/tslib/-/tslib-2.8.1.tgz",
             "integrity": "sha512-oJFu94HQb+KVduSUQL7wnpmqnfmLsOA/nAh6b6EH0wCEoK0/mPeXU6c3wKDV83MkOuHPRHtSXKKU99IBazS/2w==",
-            "dev": true,
-            "optional": true
+            "dev": true
         },
         "type-detect": {
             "version": "4.0.8",

package.json

@@ -32,7 +32,6 @@
         "build:types": "tsc --emitDeclarationOnly",
         "test": "jest",
         "test:browser": "karma start",
-        "install": "node-gyp-build",
         "prepublishOnly": "npm run build && npm test"
     },
     "keywords": [
@@ -62,6 +61,7 @@
         "node-gyp-build": "^4.8.0",
         "rollup": "^4.0.0",
         "ts-jest": "^29.4.6",
+        "tslib": "^2.8.1",
         "typescript": "^6.0.0"
     },
     "optionalDependencies": {