feat(BE): update foreign key constraints for project_chickins and adjust service logic for project flock kandang retrieval

internal/database/migrations/20251230201439_alter_project_chickins_fk_cascade.down.sql

@@ -0,0 +1,20 @@
+-- Drop CASCADE constraint
+DO $$
+BEGIN
+    IF EXISTS (
+        SELECT 1
+        FROM pg_constraint
+        WHERE conname = 'fk_project_chickins_kandang'
+        AND conrelid = 'project_chickins'::regclass
+    ) THEN
+        ALTER TABLE project_chickins
+        DROP CONSTRAINT fk_project_chickins_kandang;
+    END IF;
+END $$;
+
+-- Recreate foreign key constraint with RESTRICT (original behavior)
+ALTER TABLE project_chickins
+ADD CONSTRAINT fk_project_chickins_kandang
+FOREIGN KEY (project_flock_kandang_id)
+REFERENCES project_flock_kandangs(id)
+ON DELETE RESTRICT ON UPDATE CASCADE;

internal/database/migrations/20251230201439_alter_project_chickins_fk_cascade.up.sql

@@ -0,0 +1,20 @@
+-- Drop existing foreign key constraint with RESTRICT
+DO $$
+BEGIN
+    IF EXISTS (
+        SELECT 1
+        FROM pg_constraint
+        WHERE conname = 'fk_project_chickins_kandang'
+        AND conrelid = 'project_chickins'::regclass
+    ) THEN
+        ALTER TABLE project_chickins
+        DROP CONSTRAINT fk_project_chickins_kandang;
+    END IF;
+END $$;
+
+-- Add new foreign key constraint with CASCADE delete
+ALTER TABLE project_chickins
+ADD CONSTRAINT fk_project_chickins_kandang
+FOREIGN KEY (project_flock_kandang_id)
+REFERENCES project_flock_kandangs(id)
+ON DELETE CASCADE ON UPDATE CASCADE;