vault: use public OIDC client for CLI localhost redirect support

services/kanidm/default.nix

@@ -43,13 +43,12 @@
 
       systems.oauth2.openbao = {
         displayName = "OpenBao Secrets";
+        # Public client for CLI support (uses PKCE instead of client secret)
+        public = true;
+        enableLocalhostRedirects = true;
         # Both CLI (localhost) and Web UI callback URLs
-        originUrl = [
-          "http://localhost:8250/oidc/callback"
-          "https://vault.home.2rjus.net:8200/ui/vault/auth/oidc/oidc/callback"
-        ];
+        originUrl = "https://vault.home.2rjus.net:8200/ui/vault/auth/oidc/oidc/callback";
         originLanding = "https://vault.home.2rjus.net:8200/";
-        basicSecretFile = config.vault.secrets.openbao-oauth2.outputDir;
         preferShortUsername = true;
         # Allow groups scope for role binding
         scopeMaps.admins = [ "openid" "profile" "email" "groups" ];
@@ -87,14 +86,6 @@
     group = "kanidm";
   };
 
-  # Vault secret for OpenBao OAuth2 client secret
-  vault.secrets.openbao-oauth2 = {
-    secretPath = "services/openbao/oauth2-client-secret";
-    extractKey = "password";
-    services = [ "kanidm" ];
-    owner = "kanidm";
-    group = "kanidm";
-  };
 
   # Note: Kanidm does not expose Prometheus metrics
   # If metrics support is added in the future, uncomment: