docs(comments): no WebSocket and no CI in the present tense

The chat cut removed the only WebSocket and CI went before it, but comments still leaned on both:
`?account=` was justified by the socket, job polling by an in-process WS registry, the e2e flows as
"proxy-safe (none use the WebSocket)", and pyrightconfig named a CI container the engine contract
test never checked. Each now says what holds today (the wallet gate, no push channel, the two
contract test halves, the image build's `npm ci`, the gate).

frontend/src/lib/api/downloads.ts

@@ -200,7 +200,7 @@ export const downloadsApi = {
   // The body IS the file, and the two names ride as headers. Not a style choice: a multipart part is
   // a DECLARED body, which FastAPI reads and spools BEFORE the route's `current_user` dependency
   // runs — so with the old shape an unauthenticated caller could make the server write the whole
-  // per-file allowance to temp (P1). Headers are latin-1 on the wire, hence `encodeURIComponent`;
+  // per-file allowance to temp. Headers are latin-1 on the wire, hence `encodeURIComponent`;
   // the server percent-decodes both. Content-Type is left to the browser (the File's own type).
   uploadDownload: (
     file: File,
@@ -274,8 +274,9 @@ export const downloadsApi = {
   revokeDownloadLink: (linkId: number): Promise<{ deleted: number }> =>
     req(`/api/downloads/links/${linkId}`, { method: "DELETE" }),
   // A plain <a> navigation can't send the X-Siftlode-Account header, so pass the active
-  // account via ?account= (same wallet-gated selection the WebSocket uses) — otherwise the
-  // download resolves to the session-default account and 404s for a per-tab account's file.
+  // account via ?account= (the server honours it only for an account in this browser's wallet) —
+  // otherwise the download resolves to the session-default account and 404s for a per-tab
+  // account's file.
   downloadFileUrl: (id: number): string => {
     const a = getActiveAccount();
     return a != null ? `/api/downloads/${id}/file?account=${a}` : `/api/downloads/${id}/file`;

frontend/src/lib/api/facade.test.ts

@@ -3,7 +3,8 @@ import { describe, it, expect, beforeAll } from "vitest";
 // The façade guard: lib/api.ts is a spread-only façade over per-domain slice modules. These tests
 // mechanise the two invariants that make that structure safe — so a future edit that reintroduces
 // the interleave (a method dropped into two slices → a silent last-wins spread override) or bloats
-// the barrel (a method defined inline instead of in a domain module) fails CI instead of shipping.
+// the barrel (a method defined inline instead of in a domain module) fails the gate instead of
+// shipping.
 //
 // Scope, on purpose: this covers RUNTIME method-key collisions — the only *silent* failure mode,
 // since tsc does not flag overlapping spread keys. It deliberately does NOT cover exported-TYPE-name