web: seed a backdated event from the routines page (V-518)

A "seed" action on the existing POST /routines, taking key, value and
ago-in-hours. That route is already step-up gated and already the place a
proposed routine is accepted or dismissed, so seeding lands next to the thing
it produces. No new page and no second gated surface.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011x5DgnExQ5XZy8TZPs5bot

cmd/mavweb/main.go

@@ -1094,34 +1094,53 @@ func handleRoutines(w http.ResponseWriter, r *http.Request, core ipc.CoreAPI, se
 	var msg string
 	if r.Method == http.MethodPost {
 		action := r.FormValue("action")
-		idStr := r.FormValue("id")
-		var rid int64
-		if n, _ := fmt.Sscanf(idStr, "%d", &rid); n != 1 {
-			http.Error(w, "invalid id", http.StatusBadRequest)
-			return
-		}
-		switch action {
-		case "accept":
+		// "seed" is the one action with no routine to act on — it is what
+		// MAKES a routine (Vikunja #518), so it runs before the id parse. It
+		// lives on this route rather than a page of its own because it is
+		// already the step-up-gated surface for this table, and a second gated
+		// surface is a second thing to get wrong.
+		if action == "seed" {
 			if !stepUpOK(session, requireStepUp) {
 				http.Error(w, "step-up required: assert a passkey first", http.StatusForbidden)
 				return
 			}
-			if err := acceptRoutine(ctx, core, rid); err != nil {
-				log.Printf("routines: accept %d: %v", rid, err)
-				http.Error(w, "accept failed: "+err.Error(), http.StatusBadGateway)
+			out, err := seedRoutineEvent(ctx, core, r)
+			if err != nil {
+				log.Printf("routines: seed: %v", err)
+				http.Error(w, "seed failed: "+err.Error(), http.StatusBadGateway)
 				return
 			}
-			msg = "accepted routine — maven will remind you"
-		case "dismiss":
-			if err := core.DismissProposedRoutine(ctx, rid); err != nil {
-				log.Printf("routines: dismiss %d: %v", rid, err)
-				http.Error(w, "dismiss failed: "+err.Error(), http.StatusBadGateway)
+			msg = out
+		} else {
+			idStr := r.FormValue("id")
+			var rid int64
+			if n, _ := fmt.Sscanf(idStr, "%d", &rid); n != 1 {
+				http.Error(w, "invalid id", http.StatusBadRequest)
+				return
+			}
+			switch action {
+			case "accept":
+				if !stepUpOK(session, requireStepUp) {
+					http.Error(w, "step-up required: assert a passkey first", http.StatusForbidden)
+					return
+				}
+				if err := acceptRoutine(ctx, core, rid); err != nil {
+					log.Printf("routines: accept %d: %v", rid, err)
+					http.Error(w, "accept failed: "+err.Error(), http.StatusBadGateway)
+					return
+				}
+				msg = "accepted routine — maven will remind you"
+			case "dismiss":
+				if err := core.DismissProposedRoutine(ctx, rid); err != nil {
+					log.Printf("routines: dismiss %d: %v", rid, err)
+					http.Error(w, "dismiss failed: "+err.Error(), http.StatusBadGateway)
+					return
+				}
+				msg = "dismissed routine"
+			default:
+				http.Error(w, "unknown action", http.StatusBadRequest)
 				return
 			}
-			msg = "dismissed routine"
-		default:
-			http.Error(w, "unknown action", http.StatusBadRequest)
-			return
 		}
 	}
 	proposed, err := core.ListProposedRoutines(ctx)
@@ -1158,6 +1177,45 @@ func toRoutineViews(rs []ipc.ProposedRoutine) []routineView {
 // may do it (Vikunja #367): accepting gives the tick loop a standing new
 // reason to speak, which DESIGN.md puts at layer 3, and the button here is
 // behind step-up. Voice can park the question and dismiss, never accept.
+// seedRoutineEvent drives one backdated fact write through core (Vikunja #518),
+// so the pattern detector can be exercised against a running daemon instead of
+// over real days. Refused unless mavend was started with -allow-seed; on an
+// ordinary box the error says so and nothing is written.
+//
+// Takes "ago" rather than an absolute timestamp — hours before now, as a float
+// so a QA sitting can space four seeds three hours apart without doing clock
+// arithmetic. The detector's floor is two hours, and "0" is a legal answer
+// meaning now.
+func seedRoutineEvent(ctx context.Context, core ipc.CoreAPI, r *http.Request) (string, error) {
+	key := strings.TrimSpace(r.FormValue("key"))
+	value := strings.TrimSpace(r.FormValue("value"))
+	if key == "" || value == "" {
+		return "", errors.New("seed needs a key and a value")
+	}
+	agoHours, err := strconv.ParseFloat(strings.TrimSpace(r.FormValue("ago")), 64)
+	if err != nil {
+		return "", fmt.Errorf("seed: bad ago (hours before now): %w", err)
+	}
+	if agoHours < 0 {
+		return "", errors.New("seed: ago is hours BEFORE now, so it cannot be negative")
+	}
+	resp, err := core.SeedEvent(ctx, ipc.SeedEventReq{
+		Key:   key,
+		Value: value,
+		Ts:    time.Now().Add(-time.Duration(agoHours * float64(time.Hour))),
+	})
+	if err != nil {
+		return "", err
+	}
+	if !resp.Extracted {
+		return fmt.Sprintf("wrote fact %d, but %q is not in the action lexicon — no event, no pattern", resp.FactID, value), nil
+	}
+	if !resp.Proposed {
+		return fmt.Sprintf("seeded %s/%s (fact %d, event %d) — not enough yet to propose", resp.Action, resp.Object, resp.FactID, resp.EventID), nil
+	}
+	return fmt.Sprintf("seeded %s/%s and PROPOSED routine %d, every %.1f days", resp.Action, resp.Object, resp.RoutineID, resp.IntervalDays), nil
+}
+
 func acceptRoutine(ctx context.Context, core ipc.CoreAPI, id int64) error {
 	proposed, err := core.ListProposedRoutines(ctx)
 	if err != nil {