refactor: consolidate blockchain explorer into single app and update backup ignore patterns

- Remove standalone explorer-web app (README, HTML, package files)
- Add /web endpoint to blockchain-explorer for web interface access
- Update .gitignore to exclude application backup archives (*.tar.gz, *.zip)
- Add backup documentation files to .gitignore (BACKUP_INDEX.md, README.md)
- Consolidate explorer functionality into main blockchain-explorer application

apps/marketplace/src/lib/api.ts

@@ -0,0 +1,132 @@
+import { loadSession } from "./auth";
+
+export type DataMode = "mock" | "live";
+
+interface OfferRecord {
+  id: string;
+  provider: string;
+  capacity: number;
+  price: number;
+  sla: string;
+  status: string;
+  created_at?: string;
+  gpu_model?: string;
+  gpu_memory_gb?: number;
+  gpu_count?: number;
+  cuda_version?: string;
+  price_per_hour?: number;
+  region?: string;
+  attributes?: {
+    ollama_host?: string;
+    models?: string[];
+    vram_mb?: number;
+    driver?: string;
+    [key: string]: unknown;
+  };
+}
+
+interface OffersResponse {
+  offers: OfferRecord[];
+}
+
+export interface MarketplaceStats {
+  totalOffers: number;
+  openCapacity: number;
+  averagePrice: number;
+  activeBids: number;
+}
+
+export interface MarketplaceOffer extends OfferRecord {}
+
+const CONFIG = {
+  dataMode: (import.meta.env?.VITE_MARKETPLACE_DATA_MODE as DataMode) ?? "mock",
+  mockBase: "/mock",
+  apiBase: import.meta.env?.VITE_MARKETPLACE_API ?? "http://localhost:8081",
+  enableBids:
+    (import.meta.env?.VITE_MARKETPLACE_ENABLE_BIDS ?? "true").toLowerCase() !==
+    "false",
+  requireAuth:
+    (import.meta.env?.VITE_MARKETPLACE_REQUIRE_AUTH ?? "false").toLowerCase() ===
+    "true",
+};
+
+function buildHeaders(): HeadersInit {
+  const headers: Record<string, string> = {
+    "Cache-Control": "no-cache",
+  };
+
+  const session = loadSession();
+  if (session) {
+    headers.Authorization = `Bearer ${session.token}`;
+  }
+
+  return headers;
+}
+
+async function request<T>(path: string, init?: RequestInit): Promise<T> {
+  const response = await fetch(path, {
+    ...init,
+    headers: {
+      ...buildHeaders(),
+      ...init?.headers,
+    },
+  });
+
+  if (!response.ok) {
+    throw new Error(`Request failed: ${response.status}`);
+  }
+  return response.json() as Promise<T>;
+}
+
+export async function fetchMarketplaceStats(): Promise<MarketplaceStats> {
+  if (CONFIG.dataMode === "mock") {
+    return request<MarketplaceStats>(`${CONFIG.mockBase}/stats.json`);
+  }
+
+  return request<MarketplaceStats>(`${CONFIG.apiBase}/marketplace/stats`);
+}
+
+export async function fetchMarketplaceOffers(): Promise<MarketplaceOffer[]> {
+  if (CONFIG.dataMode === "mock") {
+    const payload = await request<OffersResponse>(`${CONFIG.mockBase}/offers.json`);
+    return payload.offers;
+  }
+
+  return request<MarketplaceOffer[]>(`${CONFIG.apiBase}/marketplace/offers`);
+}
+
+export async function submitMarketplaceBid(input: {
+  provider: string;
+  capacity: number;
+  price: number;
+  notes?: string;
+}): Promise<void> {
+  if (!CONFIG.enableBids) {
+    throw new Error("Bid submissions are disabled by configuration");
+  }
+
+  if (CONFIG.dataMode === "mock") {
+    await new Promise((resolve) => setTimeout(resolve, 600));
+    return;
+  }
+
+  if (CONFIG.requireAuth && !loadSession()) {
+    throw new Error("Authentication required to submit bids");
+  }
+
+  const response = await fetch(`${CONFIG.apiBase}/marketplace/bids`, {
+    method: "POST",
+    headers: {
+      "Content-Type": "application/json",
+      ...buildHeaders(),
+    },
+    body: JSON.stringify(input),
+  });
+
+  if (!response.ok) {
+    const message = await response.text();
+    throw new Error(message || "Failed to submit bid");
+  }
+}
+
+export const MARKETPLACE_CONFIG = CONFIG;

apps/marketplace/src/lib/auth.ts

@@ -0,0 +1,33 @@
+export interface MarketplaceSession {
+  token: string;
+  expiresAt: number;
+}
+
+const STORAGE_KEY = "marketplace-session";
+
+export function saveSession(session: MarketplaceSession): void {
+  localStorage.setItem(STORAGE_KEY, JSON.stringify(session));
+}
+
+export function loadSession(): MarketplaceSession | null {
+  const raw = localStorage.getItem(STORAGE_KEY);
+  if (!raw) {
+    return null;
+  }
+  try {
+    const data = JSON.parse(raw) as MarketplaceSession;
+    if (typeof data.token === "string" && typeof data.expiresAt === "number") {
+      if (data.expiresAt > Date.now()) {
+        return data;
+      }
+      clearSession();
+    }
+  } catch (error) {
+    console.warn("Failed to parse stored marketplace session", error);
+  }
+  return null;
+}
+
+export function clearSession(): void {
+  localStorage.removeItem(STORAGE_KEY);
+}

apps/marketplace/src/lib/utils.ts

@@ -0,0 +1,6 @@
+import { type ClassValue, clsx } from "clsx"
+import { twMerge } from "tailwind-merge"
+
+export function cn(...inputs: ClassValue[]) {
+  return twMerge(clsx(inputs))
+}