feat(diagnostics): the debug recorder — start, the pill, steps, screenshots, stop (E16 S2)

- the start dialog is the consent: level (Részletes/Teljes), what is recorded,
  retention and the cap (now served as diagnostics.session_minutes)
- the pill docks under the toasts: elapsed time, Step (an optional label,
  its own Escape layer), Screenshot (tab capture where the browser has it),
  Stop; compact on a phone
- while recording, lib/log tags every event and every request path (req,
  beacon, uploadReq via one identityHeaders) names the session; applyDiagnostics
  raises the level for the session's run and never lowers a raised one, and
  lapses at whichever ends first
- Stop sends what is waiting before the server closes the session; the cap
  says so and opens the composer
- Settings → Diagnosztika and the command palette start/step/stop it
- the evidence leaves the log upload's own request lines out
- the step shortcut is deliberately palette-only: the keymap's D1 rule bars a
  new modifier chord, and a bare letter collides with the players'

frontend/src/components/DiagnosticsSettings.tsx

@@ -10,6 +10,7 @@ import InlineNotice from "./ui/InlineNotice";
 import SegmentedToggle from "./ui/SegmentedToggle";
 import { Section, SettingRow } from "./ui/form";
 import MyLogViewer from "./MyLogViewer";
+import { RecorderSettings } from "./DebugRecorder";
 
 const LEVELS: readonly DiagnosticsLevel[] = ["INFO", "DEBUG", "TRACE"];
 
@@ -181,6 +182,12 @@ export default function DiagnosticsSettings() {
         )}
       </Section>
 
+      {!me.is_demo && (
+        <Section title={t("recorder.settings.title")}>
+          <RecorderSettings />
+        </Section>
+      )}
+
       <Section title={t("settings.myLog.title")}>
         <MyLogViewer />
       </Section>