feat(auth): add option to disable built-in login when using OIDC (#1908)

* feat(auth): disable built-in login by config

* cleanup config

* fix(web): prevent login form flash by waiting for OIDC config

* refactor(config): standardize OIDC TOML format

- Adds camelCase TOML tags to OIDC config struct while keeping mapstructure tags for backward compatibility
- Updates config template to use camelCase format

* refactor: kyles changes

* refactor: prefix disablebuiltinlogin with oidc

* docs: revert format change

---------

Co-authored-by: ze0s <43699394+zze0s@users.noreply.github.com>

config.toml

@@ -72,19 +72,22 @@ sessionSecret = "secret-session-key"
 # OpenID Connect Configuration
 #
 # Enable OIDC authentication
-#oidc_enabled = false
-
+#oidcEnabled = false
+#
 # OIDC Issuer URL (e.g. https://auth.example.com)
-#oidc_issuer = ""
-
+#oidcIssuer = ""
+#
 # OIDC Client ID
-#oidc_client_id = ""
-
+#oidcClientId = ""
+#
 # OIDC Client Secret
-#oidc_client_secret = ""
-
+#oidcClientSecret = ""
+#
 # OIDC Redirect URL (e.g. http://localhost:7474/api/auth/oidc/callback)
-#oidc_redirect_url = ""
+#oidcRedirectUrl = ""
+#
+# Disable Built In Login Form (only works when using external auth)
+#oidcDisableBuiltInLogin = false
 
 # Metrics
 #
@@ -93,11 +96,11 @@ sessionSecret = "secret-session-key"
 
 # Metrics server host
 #
-# metricsHost = "127.0.0.1"
+#metricsHost = "127.0.0.1"
 
 # Metrics server port
 #
-# metricsPort = "9074"
+#metricsPort = "9074"
 
 # Metrics basic auth
 #