Recap: readable transcript + topic sections + meeting extras (gateway LLM)

New 'Recap' phase — turns speakers.json into a human-readable recap, leveraging
recap-relay's proven logic/prompts but calling the Spark gateway's OpenAI-compatible
/v1/chat/completions directly (same host/TLS as label-merge; Qwen3-35B). We start
from already-named speakers (label-merge), so recap-relay's speaker clustering +
name-inference are skipped entirely.

- GatewayLLMClient: /v1/chat/completions (JSON mode), model discovery via
  /api/endpoints, TLS-skip reuse, 503 retry, sequential.
- RecapAnalyzer: speakers.json → numbered [N] (MM:SS) Name: text transcript →
  time-windowed analyze (single window for short calls, 18min/2min overlap for long)
  → stitch/dedup topic sections → meeting extras (TLDR/decisions/action_items/
  open_questions/key_quotes). Defensive JSON parsing of LLM output.
- RecapRenderer: writes transcript.md + a self-contained dark-theme recap.html
  (topic sections w/ collapsible transcripts, extras panels, speaker color chips,
  full timestamped speaker-attributed transcript, print styles).
- SessionController.buildRecap: best-effort after speakers.json (gated by
  settings.recapEnabled); surfaces recapURL → menu 'Open recap'. Skips silently if
  the gateway has no LLM. Settings toggle added.

Validated END-TO-END on the real Meet session against the live gateway: dual-channel
transcription → 3 topic sections + accurate TLDR + key quotes; 'Go Bitcoin'
correctly attributed to the remote speaker. 46/46 XCTest (10 new).

Ten31Transcripts/UI/SettingsView.swift

@@ -25,7 +25,8 @@ struct SettingsView: View {
                 TextField("Your name", text: $settings.selfName)
                     .textFieldStyle(.roundedBorder)
                 Toggle("Auto-send recordings to backend", isOn: $settings.autoSendOnStop)
-                Text("Your name labels the mic-VAD \"self\" spans. Auto-send transcribes each recording on stop.")
+                Toggle("Build readable recap (topics + highlights)", isOn: $settings.recapEnabled)
+                Text("Your name labels your mic channel. Auto-send transcribes on stop; the recap writes transcript.md + recap.html.")
                     .font(.caption)
                     .foregroundStyle(.secondary)
             }