feat(series): choose open series or club members only for series points

Who scores is now an explicit per-series choice: every driver (default)
or club members only, with the club field shown only for the latter.
Series saved with a club keep members-only scoring. README updated.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "rc-racecore",
-  "version": "1.35.1",
+  "version": "1.36.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "rc-racecore",
-      "version": "1.35.1",
+      "version": "1.36.0",
       "hasInstallScript": true,
       "dependencies": {
         "better-sqlite3": "^12.11.1",