Rename ecosplay client, fix redirect URIs, set admin user real name

- Rename OIDC client ecosplay-web -> ecosplay_web in the realm import
  JSON. The client is used by the internal e-cosplay site for OAuth.
- Replace wildcard redirect URIs with the two exact callbacks:
  https://www.e-cosplay.fr/oauth/keycloak and
  https://cos.local/oauth/keycloak. webOrigins and post-logout URIs
  follow the same hosts.
- Add helpers to sync.sh (client_internal_id, rename_client,
  set_client_uris) and a reconciliation step that renames any legacy
  ecosplay-web -> ecosplay_web and idempotently re-applies the URIs
  on every run, so live installs are migrated automatically.
- Set the bootstrap admin user's real first/last name (jovann Serreau)
  in both the env vars and the realm import JSON.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

realms/ecosplay-realm.json

@@ -71,8 +71,8 @@
     {
       "username": "jovann@siteconseil.fr",
       "email": "jovann@siteconseil.fr",
-      "firstName": "Jovann",
-      "lastName": "SiteConseil",
+      "firstName": "jovann",
+      "lastName": "Serreau",
       "enabled": true,
       "emailVerified": true,
       "credentials": [
@@ -92,19 +92,19 @@
 
   "clients": [
     {
-      "clientId": "ecosplay-web",
+      "clientId": "ecosplay_web",
       "name": "E-Cosplay Web",
-      "description": "Application web principale e-cosplay.fr",
+      "description": "Application web principale e-cosplay.fr (login site interne)",
       "enabled": true,
       "publicClient": false,
       "secret": "change-me-in-admin-console",
       "redirectUris": [
-        "https://www.e-cosplay.fr/*",
-        "https://e-cosplay.fr/*"
+        "https://www.e-cosplay.fr/oauth/keycloak",
+        "https://cos.local/oauth/keycloak"
       ],
       "webOrigins": [
         "https://www.e-cosplay.fr",
-        "https://e-cosplay.fr"
+        "https://cos.local"
       ],
       "protocol": "openid-connect",
       "standardFlowEnabled": true,
@@ -113,7 +113,7 @@
       "serviceAccountsEnabled": false,
       "frontchannelLogout": true,
       "attributes": {
-        "post.logout.redirect.uris": "https://www.e-cosplay.fr/*##https://e-cosplay.fr/*",
+        "post.logout.redirect.uris": "https://www.e-cosplay.fr/*##https://cos.local/*",
         "pkce.code.challenge.method": "S256"
       }
     }