docs(architecture): note per-stream diarization in the stop data flow (FR-SPK)

docs/02-architecture.md

@@ -84,10 +84,14 @@ issues from feature briefs.
 4. Provisional speaker turns (from cheap segmentation) tag segments live; the user may name a
    speaker, applied immediately to past/future segments (FR-SPK-2).
 5. The notes view renders Markdown that updates as segments arrive (FR-NOTE-1, FR-NOTE-6).
-6. On `stop_recording`: finalize the WAV; run full `diarization`, align speaker IDs to segments,
-   apply name mappings; persist transcript JSON + metadata via `storage` (FR-STORE-1). If "Record
-   this meeting" is **off**, delete the working WAV **after** the transcript is finalized; if **on**,
-   keep it as `audio.wav` (ADR-0009, FR-REC-1/4).
+6. On `stop_recording`: finalize the WAV; run `diarization`, align speaker IDs to segments,
+   apply name mappings; persist transcript JSON + metadata via `storage` (FR-STORE-1). When the mic
+   is on, attribution is **per-stream** (ADR-0005 Phase 3, FR-SPK): the mic-activity timeline that
+   `audio` recorded (in `audio.wav` frame time, where the mic is folded into the loopback writer) is
+   the user's "You" spans directly, and sherpa clusters only the far side — the recording diarized
+   with those ranges masked out. Blind whole-signal clustering + voiceprint is the mic-off fallback.
+   If "Record this meeting" is **off**, delete the working WAV **after** the transcript is finalized;
+   if **on**, keep it as `audio.wav` (ADR-0009, FR-REC-1/4).
 7. If an LLM provider is configured: `llm` builds a prompt (transcript + metadata + template),
    streams a summary/decisions/action-items into the summary panel (FR-LLM-2/4).
 8. Action items are parsed and presented for confirmation; confirmed ones persist and may raise