feat: add watchlist dashboard workflow

apps/web/src/lib/api.ts

@@ -44,6 +44,22 @@ export type MarketOverview = {
   highest_supply_risk_area: AreaScoreSummary | null;
 };
 
+export type WatchlistItem = {
+  watchlist_item_id: number;
+  neighborhood_id: string | null;
+  area_id: string | null;
+  target_price_psm: number | null;
+  status: string;
+  notes: string;
+};
+
+export type CreateWatchlistItem = {
+  area_id?: string;
+  neighborhood_id?: string;
+  target_price_psm?: number;
+  notes?: string;
+};
+
 const API_BASE_URL =
   process.env.NEXT_PUBLIC_API_BASE_URL?.replace(/\/$/, "") ?? "http://127.0.0.1:8080";
 
@@ -55,8 +71,33 @@ export async function fetchAreaScores(month: string): Promise<AreaScore[]> {
   return fetchJson(`/api/v1/areas/scores?month=${encodeURIComponent(month)}`);
 }
 
-async function fetchJson<T>(path: string): Promise<T> {
-  const response = await fetch(`${API_BASE_URL}${path}`);
+export async function fetchWatchlistItems(): Promise<WatchlistItem[]> {
+  return fetchJson("/api/v1/watchlist");
+}
+
+export async function createWatchlistItem(
+  payload: CreateWatchlistItem,
+): Promise<WatchlistItem> {
+  return fetchJson("/api/v1/watchlist", {
+    method: "POST",
+    body: JSON.stringify(payload),
+  });
+}
+
+export async function archiveWatchlistItem(id: number): Promise<WatchlistItem> {
+  return fetchJson(`/api/v1/watchlist/${id}`, {
+    method: "DELETE",
+  });
+}
+
+async function fetchJson<T>(path: string, init?: RequestInit): Promise<T> {
+  const response = await fetch(`${API_BASE_URL}${path}`, {
+    ...init,
+    headers: {
+      "Content-Type": "application/json",
+      ...init?.headers,
+    },
+  });
   if (!response.ok) {
     throw new Error(`API request failed with ${response.status}`);
   }