feat: add is_admin to User, count_users, ProviderConfigRepository trait, admin migration

k-tv-backend/domain/src/repositories.rs

@@ -39,6 +39,24 @@ pub trait UserRepository: Send + Sync {
 
     /// Delete a user by their ID
     async fn delete(&self, id: Uuid) -> DomainResult<()>;
+
+    /// Count total number of users (used for first-user admin promotion)
+    async fn count_users(&self) -> DomainResult<u64>;
+}
+
+#[derive(Debug, Clone)]
+pub struct ProviderConfigRow {
+    pub provider_type: String,
+    pub config_json: String,
+    pub enabled: bool,
+    pub updated_at: String,
+}
+
+#[async_trait]
+pub trait ProviderConfigRepository: Send + Sync {
+    async fn get_all(&self) -> DomainResult<Vec<ProviderConfigRow>>;
+    async fn upsert(&self, row: &ProviderConfigRow) -> DomainResult<()>;
+    async fn delete(&self, provider_type: &str) -> DomainResult<()>;
 }
 
 /// Repository port for `Channel` persistence.