refactor: codebase opschoning — type safety, error handling, central config, page splits

- categorie A: alle catch(e: any) → catch(e: unknown) met instanceof check
- categorie B: stille .catch() logging toegevoegd (SWRegister, admin, upload, auth)
- categorie C: hardcoded 192.168.1.176 IPs vervangen door env var defaults
- categorie D: page files >250L gesplitst (history, settings, explorer, admin/payment,
  ipns, users, upload, dashboard) in helpers/components
- categorie E: eslint-disable vervangen in SearchInput.tsx
- src/lib/config.ts centrale config module (localhost defaults)
- CSP in next.config.ts dynamisch via env var
- deploy.sh: geen hardcoded IP meer (REQUIRED arg)
- lib/api/ lib/auth/ lib/wallet/ lib/search-index/ lib/storage/ gesplitst in modules
- ongebruikte bestanden verwijderd: api.ts, auth.tsx, wallet.ts, search-index.ts,
  PaymentPanel.tsx, SearchBar.tsx, proxy.ts, serve-static.js

src/lib/api/explorer.ts

@@ -0,0 +1,30 @@
+/* ── IPFS Portal API — IPFS Explorer ── */
+
+import { apiFetch, API_BASE } from './client';
+
+export interface IPFSEntry {
+  name: string;
+  type: 'file' | 'dir';
+  size: number;
+  hash: string;
+}
+
+export async function explorerLs(cid: string): Promise<IPFSEntry[]> {
+  return apiFetch(`/explorer/ls/${encodeURIComponent(cid)}`, { method: 'POST' });
+}
+
+export async function explorerCat(cid: string): Promise<string> {
+  const res = await fetch(`${API_BASE}/api/explorer/cat/${encodeURIComponent(cid)}`, {
+    method: 'POST',
+    credentials: 'include',
+  });
+  if (!res.ok) {
+    const text = await res.text().catch(() => '');
+    throw new Error(`${res.status} ${res.statusText}: ${text.slice(0, 200)}`);
+  }
+  return res.text();
+}
+
+export async function explorerStat(cid: string): Promise<Record<string, unknown>> {
+  return apiFetch(`/explorer/stat/${encodeURIComponent(cid)}`, { method: 'POST' });
+}