feat(frontend): integrate inter-project material transfer into ChangeInventoryPage and ArrivalsPage

- Add PROJECT_TRANSFER tab under reductions in ChangeInventoryPage
- Render complete material spec form with destination project selector
- Show matching stock preview in source warehouse
- Add transfer history table with in-transit edit modal and cancellation dialog
- Add incoming transfer cards in ArrivalsPage with 100% full delivery allocation

frontend/src/lib/api.ts

@@ -30,6 +30,10 @@ import type {
   Supplier,
   TransactionType,
   Warehouse,
+  ProjectTransfer,
+  ProjectTransferCreateIn,
+  ProjectTransferUpdateIn,
+  ProjectTransferReceiveIn,
 } from "./types";
 
 const BASE_URL = (import.meta.env?.VITE_API_BASE_URL as string | undefined)?.trim() || "/api/v1";
@@ -1746,4 +1750,28 @@ export const apiV26 = {
         attributes: [],
       }),
   },
+
+  projectTransfers: {
+    list: async (projectId?: string | null, direction: "outgoing" | "incoming" | "all" = "all", status?: string): Promise<ProjectTransfer[]> => {
+      const q = new URLSearchParams();
+      if (projectId) q.set("project_id", projectId);
+      if (direction) q.set("direction", direction);
+      if (status) q.set("status", status);
+      const qs = q.toString() ? `?${q.toString()}` : "";
+      return getData<ProjectTransfer[]>(`/inventory/project-transfers${qs}`);
+    },
+    get: async (id: string, projectId?: string | null): Promise<ProjectTransfer> =>
+      getData<ProjectTransfer>(projectId ? `/inventory/project-transfers/${id}?project_id=${projectId}` : `/inventory/project-transfers/${id}`),
+    create: async (body: ProjectTransferCreateIn, projectId?: string | null): Promise<ProjectTransfer> =>
+      postData<ProjectTransfer>(projectId ? `/inventory/project-transfers?project_id=${projectId}` : `/inventory/project-transfers`, body),
+    update: async (id: string, patch: ProjectTransferUpdateIn, projectId?: string | null): Promise<ProjectTransfer> =>
+      patchData<ProjectTransfer>(projectId ? `/inventory/project-transfers/${id}?project_id=${projectId}` : `/inventory/project-transfers/${id}`, patch),
+    delete: async (id: string, projectId?: string | null): Promise<{ ok: boolean; message: string }> =>
+      deleteData(projectId ? `/inventory/project-transfers/${id}?project_id=${projectId}` : `/inventory/project-transfers/${id}`),
+    onTheWay: async (projectId?: string | null): Promise<ProjectTransfer[]> =>
+      getData<ProjectTransfer[]>(projectId ? `/pm/transfers/on-the-way?project_id=${projectId}` : `/pm/transfers/on-the-way`),
+    receive: async (id: string, body: ProjectTransferReceiveIn, projectId?: string | null): Promise<ProjectTransfer> =>
+      postData<ProjectTransfer>(projectId ? `/inventory/project-transfers/${id}/receive?project_id=${projectId}` : `/inventory/project-transfers/${id}/receive`, body),
+  },
 };
+