Add region target/budget/tax-rule/agency-map/hierarchy/dashboard APIs

Extends RegionService, RegionRepository, and RegionController with the
endpoints from mainPlan.md sec 2 beyond plain CRUD: setRegionalTarget,
setRegionalBudget, mapAgencyToRegion, setRegionalTaxRule,
getRegionHierarchy, and getRegionDashboard. Target/budget/tax-rule
mutation is gated to users with region scope at RegionalManager level
or RegionalAgency level across all regions; mapAgencyToRegion links an
existing User holding the RegionalAgency role rather than introducing
a separate agency entity, matching the convention already used by
Claim.FK_AgencyUserId elsewhere in the codebase.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

Distribution/Features/Region/IRegionRepository.cs

@@ -7,4 +7,26 @@ public interface IRegionRepository
     Task AddAsync(Models.Region entity);
     void Update(Models.Region entity);
     void Remove(Models.Region entity);
+
+    Task<Models.RegionalTarget?> GetTargetAsync(Guid regionId, string period);
+    Task AddTargetAsync(Models.RegionalTarget target);
+    void UpdateTarget(Models.RegionalTarget target);
+
+    Task<Models.RegionalBudget?> GetBudgetAsync(Guid regionId, string period);
+    Task AddBudgetAsync(Models.RegionalBudget budget);
+    void UpdateBudget(Models.RegionalBudget budget);
+
+    Task<Models.RegionAgencyMap?> GetAgencyMapAsync(Guid regionId, Guid agencyUserId);
+    Task AddAgencyMapAsync(Models.RegionAgencyMap map);
+
+    Task<Models.RegionalTaxRule?> GetTaxRuleAsync(Guid regionId);
+    Task AddTaxRuleAsync(Models.RegionalTaxRule rule);
+    void UpdateTaxRule(Models.RegionalTaxRule rule);
+
+    Task<int?> GetUserRoleLevelAsync(Guid userId);
+
+    Task<List<Models.Route>> GetRoutesAsync(Guid regionId);
+    Task<List<Models.Store>> GetStoresByRouteIdsAsync(List<Guid> routeIds);
+
+    Task<List<Models.Order>> GetOrdersForDashboardAsync(Guid regionId, DateTime periodStart, DateTime periodEndExclusive);
 }