feat(web): emailgen events in Orchestrator page

The SSE pipe at /orchestrator/events/stream was already streaming
'orchestrator.email.{decky_uuid}' events (the subscription is for the
'orchestrator.>' wildcard), but the consumer side dropped them on the
floor.  Three fixes to close the loop:

* useOrchestratorStream.ts now registers an 'email' SSE listener — the
  EventSource silently ignores frames whose event name has no listener,
  so missing this entry meant every email frame was dropped before
  reaching the page's onEvent handler.

* /api/v1/orchestrator/events accepts kind=email and dispatches to
  list_orchestrator_emails, adapting rows to the existing wire shape:
  subject -> action, sender_email -> src_decky_uuid, recipient_email
  -> dst_decky_uuid, plus email-specific extras (thread_id, language,
  mail_decky_uuid, message_id, in_reply_to) ride along as top-level
  keys.

* Orchestrator.tsx gains an 'email' tab in the kind filter and a
  branch in the row renderer / inspector that:
   - shows full sender / recipient (no UUID truncation),
   - chips the language code next to the subject,
   - relabels ACTION as SUBJECT in the inspector and surfaces
     thread / in-reply-to / mail-decky details.

The 'all' tab continues to show traffic+file only (today's behavior);
operators see emails by switching to the email tab.  A union view at
the API layer is the obvious follow-up but not necessary for now.

decnet/web/router/orchestrator/api_list_events.py

@@ -1,7 +1,26 @@
 """GET /api/v1/orchestrator/events — paginated orchestrator activity.
 
+Two underlying tables back this endpoint:
+
+* ``orchestrator_events`` — SSH traffic + file ops (kind = ``traffic``, ``file``)
+* ``orchestrator_emails`` — emailgen-generated EMLs (kind = ``email``)
+
+When the caller filters ``kind=email`` we dispatch to the emails table
+and adapt rows into the same wire shape the dashboard already renders.
+The mapping is:
+
+* ``action``           ← email subject
+* ``src_decky_uuid``   ← sender_email
+* ``dst_decky_uuid``   ← recipient_email
+* ``protocol``         ← ``"smtp"``
+* email-specific fields (``thread_id``, ``language``, ``mail_decky_uuid``,
+  ``message_id``, ``in_reply_to``) ride along as top-level keys for the
+  inspector / future per-email views; the existing event renderer
+  ignores anything it doesn't recognise.
+
 Mirrors :mod:`decnet.web.router.campaigns.api_list_campaigns`. The
-orchestrator worker is the sole writer; this surface is read-only.
+orchestrator + emailgen workers are the sole writers; this surface is
+read-only.
 """
 from typing import Any, Optional
 
@@ -13,6 +32,32 @@ from decnet.web.dependencies import repo, require_viewer
 router = APIRouter()
 
 
+def _adapt_email_row(e: dict[str, Any]) -> dict[str, Any]:
+    """Reshape an ``orchestrator_emails`` row into the wire shape the
+    dashboard's event table understands, while carrying the email-only
+    fields through as extras."""
+    return {
+        "uuid": e.get("uuid"),
+        "ts": e.get("ts"),
+        "kind": "email",
+        "protocol": "smtp",
+        "action": e.get("subject", ""),
+        "src_decky_uuid": e.get("sender_email"),
+        "dst_decky_uuid": e.get("recipient_email"),
+        "success": bool(e.get("success")),
+        "payload": e.get("payload", "{}"),
+        # Email-specific extras (renderer keys off ``kind == 'email'``).
+        "subject": e.get("subject"),
+        "sender_email": e.get("sender_email"),
+        "recipient_email": e.get("recipient_email"),
+        "language": e.get("language"),
+        "thread_id": e.get("thread_id"),
+        "mail_decky_uuid": e.get("mail_decky_uuid"),
+        "message_id": e.get("message_id"),
+        "in_reply_to": e.get("in_reply_to"),
+    }
+
+
 @router.get(
     "/orchestrator/events",
     tags=["Orchestrator"],
@@ -26,12 +71,17 @@ router = APIRouter()
 async def list_orchestrator_events(
     limit: int = Query(50, ge=1, le=1000),
     offset: int = Query(0, ge=0, le=2147483647),
-    kind: Optional[str] = Query(None, pattern="^(traffic|file)$"),
+    kind: Optional[str] = Query(None, pattern="^(traffic|file|email)$"),
     user: dict = Depends(require_viewer),
 ) -> dict[str, Any]:
     """Paginated orchestrator-event list, newest first."""
-    data = await repo.list_orchestrator_events(
-        limit=limit, offset=offset, kind=kind,
-    )
-    total = await repo.count_orchestrator_events(kind=kind)
+    if kind == "email":
+        emails = await repo.list_orchestrator_emails(limit=limit, offset=offset)
+        total = await repo.count_orchestrator_emails()
+        data = [_adapt_email_row(e) for e in emails]
+    else:
+        data = await repo.list_orchestrator_events(
+            limit=limit, offset=offset, kind=kind,
+        )
+        total = await repo.count_orchestrator_events(kind=kind)
     return {"total": total, "limit": limit, "offset": offset, "data": data}