Hash the 40k hidden-players list and drop the old PayPal block

Hidden players are now matched by a hash of their full name or nickname
(src/hide.js) so the names aren't readable in the source or bundle.
Also removes the commented-out PayPal section from the Kingmaker
sign-up page.

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

sites/40k-rankings/README.md

@@ -53,8 +53,11 @@ Everything you'd normally change is in the `CONFIG` block at the top of
 - `teamId`: the BCP team whose members are shown
 - `leagueId` / `regionId`: which ITC league and region to rank against
 - `lmcLeagueId`: the Lord Marshal Conference league used for the LMC columns
-- `blacklistNames`: players to hide from the board (full name or nickname,
-  case-insensitive)
+- `hiddenNameHashes`: players to hide from the board, stored as hashes of
+  their full name or nickname so the names aren't readable in the source. The
+  comment at the top of `src/hide.js` has a one-line command to hash a name.
+  This only obfuscates: the roster is public, so anyone could hash every
+  member's name to find who's hidden.
 - `memberIds`: fallback roster, used if the team endpoint ever stops returning
   members without auth
 - `useSample`: set to `true` to render placeholder rows with no network calls
@@ -62,6 +65,7 @@ Everything you'd normally change is in the `CONFIG` block at the top of
 ## Files
 
 - `index.html`, `src/main.js`, `src/style.css`: the page
+- `src/hide.js`: name hashing for `hiddenNameHashes`
 - `nav.html`: this site's header nav entries (see the root README)
 - `public/elo-data.json`: generated ELO data. Don't edit it by hand; the
   weekly sync overwrites it.