fix(ci): ship .npmrc in published package so legacy-peer-deps applies to consumers (#11544) (#12699)

Merged — one line, zero risk, and it costs nothing to have.

One caveat recorded so nobody later reads this as "#11544 is solved": npm resolves config from the *installing* project's directory, the user config and the global config — it does not read the `.npmrc` shipped inside a dependency's tarball. So `legacy-peer-deps=true` traveling in the package will not change how `npm install -g omniroute` resolves peers on the consumer side. Our own `scripts/build/postinstall.mjs` does shell out to `npm rebuild` / `npm install better-sqlite3`, but with cwd set to `dist/`, so the package-root `.npmrc` is not in scope there either.

Keeping it anyway: it makes the published tree self-documenting, and someone debugging inside an extracted package gets the same retry budget we use in CI. But #11544 (`npm install -g omniroute` failing on Windows, "root cause unclear from log") still needs the actual `npm-debug.log` from the reporter before it can be closed.

Rebased onto `release/v3.8.51`; `package.json` re-parses and the `files` array kept both `config/i18n.json` and the new entry. Thanks.

package.json

@@ -22,6 +22,7 @@
     "src/types/",
     ".env.example",
     "config/i18n.json",
+    ".npmrc",
     "scripts/build/postinstall.mjs",
     "scripts/build/fixPlaywrightAndroid.mjs",
     "bin/cli/runtime/",