feat: add import templates

apps/api/src/handlers.rs

@@ -3,11 +3,12 @@ use axum::Json;
 use serde::Serialize;
 
 use crate::error::{ApiError, ApiResult};
+use crate::import_templates::validate_import_payload;
 use crate::models::{
     AreaScore, AreaScoreSummary, CreateDataSource, CreateIngestionRun, CreateWatchlistItem,
-    DataSource, FinishIngestionRun, IngestionRun, IngestionRunQuery, MarketOverview, MonthQuery,
-    Neighborhood, NeighborhoodQuery, NeighborhoodScore, NeighborhoodScoreQuery,
-    UpdateWatchlistItem, WatchlistItem,
+    DataSource, FinishIngestionRun, ImportValidationRequest, ImportValidationResponse,
+    IngestionRun, IngestionRunQuery, MarketOverview, MonthQuery, Neighborhood, NeighborhoodQuery,
+    NeighborhoodScore, NeighborhoodScoreQuery, UpdateWatchlistItem, WatchlistItem,
 };
 use crate::state::AppState;
 
@@ -32,6 +33,13 @@ pub async fn ready(State(state): State<AppState>) -> ApiResult<Json<HealthRespon
     }))
 }
 
+pub async fn validate_import(
+    Json(payload): Json<ImportValidationRequest>,
+) -> ApiResult<Json<ImportValidationResponse>> {
+    let result = validate_import_payload(&payload).map_err(ApiError::BadRequest)?;
+    Ok(Json(result))
+}
+
 pub async fn list_area_scores(
     State(state): State<AppState>,
     Query(query): Query<MonthQuery>,