adventure: fix three review findings on the who page

- timelineLine named the viewer as their own rival on a lost duel: a
  rival_result arrives on the loser's page via the opponent column, so
  naming the opponent field pointed at themselves. Thread the page
  character's name through and name the other party.
- buildMapView drew a frontier room twice when two visited rooms both
  had a door to it (Nodes carried the id twice). Place each id once.
- proseGuard's board query ran before the IsGUIDSeen dedup, so a retried
  dispatch paid for it and threw it away. Check dedup first.

internal/web/adventure.go

@@ -108,6 +108,15 @@ func (s *Server) handleAdventureIngest(w http.ResponseWriter, r *http.Request) {
 		http.Error(w, "unknown event_type", http.StatusBadRequest)
 		return
 	}
+	// Idempotent: a re-delivered fact (gogobee retry) is a no-op success. Checked
+	// before the prose-guard because the guard runs a board query (KnownCharacterNames);
+	// a retried dispatch we already have a story for should cost nothing.
+	if storage.IsGUIDSeen(f.GUID) {
+		w.WriteHeader(http.StatusOK)
+		_, _ = w.Write([]byte("duplicate"))
+		return
+	}
+
 	// Prefer gogobee's LLM prose when it is present and safe. Both fields must be
 	// supplied — a half-authored dispatch is not a voice, and mixing an LLM
 	// headline with a template lede reads as two writers. The guard is what makes
@@ -122,13 +131,6 @@ func (s *Server) handleAdventureIngest(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	// Idempotent: a re-delivered fact (gogobee retry) is a no-op success.
-	if storage.IsGUIDSeen(f.GUID) {
-		w.WriteHeader(http.StatusOK)
-		_, _ = w.Write([]byte("duplicate"))
-		return
-	}
-
 	// A fact with no occurred_at would otherwise be stored at the Unix epoch:
 	// dated 1970 on the permalink, pinned to the bottom of the section, and
 	// outside every digest window. Treat "missing" as "now".

internal/web/who.go

@@ -213,7 +213,7 @@ func (s *Server) handleAdventureWho(w http.ResponseWriter, r *http.Request) {
 		if page.MoreHistory {
 			events = events[:timelineCap]
 		}
-		page.Timeline = buildTimeline(s, events)
+		page.Timeline = buildTimeline(s, entry.Name, events)
 	}
 
 	// Owner enrichment: only when the signed-in user's localpart owns this exact
@@ -279,14 +279,14 @@ func (s *Server) handleAdventureWhoAPI(w http.ResponseWriter, r *http.Request) {
 // ever: Josie brings down the Rotmother"), and forty of those stacked in a column
 // read as a wall of shouting. The trail wants the noun, not the announcement. It
 // also saves a join back to stories for every row.
-func buildTimeline(s *Server, events []storage.AdvEvent) []timelineEntry {
+func buildTimeline(s *Server, subject string, events []storage.AdvEvent) []timelineEntry {
 	out := make([]timelineEntry, 0, len(events))
 	for _, e := range events {
 		label, emoji := advEventMeta(e.EventType)
 		out = append(out, timelineEntry{
 			Emoji:     emoji,
 			Label:     label,
-			Line:      timelineLine(e),
+			Line:      timelineLine(subject, e),
 			When:      time.Unix(e.OccurredAt, 0).UTC().Format("Jan 2, 2006"),
 			Permalink: s.advPermalink(e.GUID),
 			// A realm-first hoard is the treasure worth an eye; a plain find rides
@@ -301,7 +301,7 @@ func buildTimeline(s *Server, events []storage.AdvEvent) []timelineEntry {
 // timelineLine is the short "what" of a fact: the monster, the zone, the rival.
 // Empty is fine — the label and emoji already carry the event, and inventing
 // filler for a fact that carries no nouns would just be noise.
-func timelineLine(e storage.AdvEvent) string {
+func timelineLine(subject string, e storage.AdvEvent) string {
 	inZone := func(s string) string {
 		if e.Zone == "" {
 			return s
@@ -321,8 +321,16 @@ func timelineLine(e storage.AdvEvent) string {
 		}
 		return e.Zone
 	case "rival_result", "pete_duel_win", "pete_duel_loss":
-		if e.Opponent != "" {
-			return "vs " + e.Opponent
+		// Name the *other* party. On the winner's page the rival is the opponent;
+		// on the loser's page this fact arrives via the opponent column, so the
+		// rival is the subject — naming e.Opponent there would point the viewer at
+		// themselves. Pete duels carry no character opponent, so this stays empty.
+		other := e.Opponent
+		if e.Opponent == subject {
+			other = e.Subject
+		}
+		if other != "" && other != subject {
+			return "vs " + other
 		}
 		return ""
 	case "milestone":

internal/web/who_map.go

@@ -116,7 +116,16 @@ func buildMapView(m *whoMap) *mapView {
 	// Group nodes by depth column, each column ordered by first appearance.
 	maxDepth := 0
 	byCol := map[int][]string{}
+	placed := make(map[string]bool, len(m.Nodes))
 	for _, n := range m.Nodes {
+		// Two visited rooms can both list a door to the same withheld frontier
+		// room, so the same id can appear twice in Nodes. Place it once, or it
+		// draws as two overlapping discs and its edges resolve to whichever copy
+		// landed last.
+		if placed[n.ID] {
+			continue
+		}
+		placed[n.ID] = true
 		d := depth[n.ID]
 		byCol[d] = append(byCol[d], n.ID)
 		if d > maxDepth {