Give each event its own page and show bodies the same everywhere (closes #369)

Each event now has its own page at /hook/ID/events/EVENTID, behind the login, showing its details, its whole body and every delivery; a resubmitted copy links to its original's page. The recent events on the webhook page link there and expand to show their bodies, only the newest expanded on load. One renderer and one template show a body the same way in the recent events, the event log and the event's page: whole up to 32 KiB, cut there in the two lists with links to the event's page and the download; JSON pretty-printed unless that would grow it past four times plus 1 KiB; over 200 lines in a scrolling box; a body holding NUL or control characters treated as binary and never dumped raw.

Model: opus-5-5

internal/handlers/source_management.go

@@ -1022,10 +1022,10 @@ func (h *Handlers) HandleSourceLogs() http.HandlerFunc {
 // view, which renders its target as a blank name.
 //
 // This map is historical display only. It is built for the event
-// log page and reaches nothing but DeliveryView.Target: the
-// target list on the source detail page, the edit form and the
-// replay path each resolve targets themselves, and a deleted row
-// is refused there as before.
+// log and an event's own page, and reaches nothing but
+// DeliveryView.Target: the target list on the source detail page,
+// the edit form and the replay path each resolve targets
+// themselves, and a deleted row is refused there as before.
 func (h *Handlers) loadTargetMap(
 	webhookID string,
 ) (map[string]eventLogTarget, error) {
@@ -1081,10 +1081,8 @@ func (h *Handlers) loadEventsWithDeliveries(
 	targetMap map[string]eventLogTarget,
 	page int,
 ) ([]EventLogView, int64, bool) {
-	var result []EventLogView
-
 	if !h.dbMgr.DBExists(webhook.ID) {
-		return result, 0, true
+		return nil, 0, true
 	}
 
 	webhookDB, err := h.dbMgr.GetDB(webhook.ID)
@@ -1100,7 +1098,26 @@ func (h *Handlers) loadEventsWithDeliveries(
 		webhookDB, webhook.ID, page,
 	)
 
-	result = make([]EventLogView, len(rows))
+	result, ok := h.eventLogViews(
+		w, r, webhookDB, webhook.ID, rows, targetMap,
+	)
+
+	return result, totalEvents, ok
+}
+
+// eventLogViews projects loaded events for rendering, each with
+// its deliveries and how many times it has been resubmitted. Like
+// loadEventsWithDeliveries, it reports false once it has answered
+// the request with an error.
+func (h *Handlers) eventLogViews(
+	w http.ResponseWriter,
+	r *http.Request,
+	webhookDB *gorm.DB,
+	webhookID string,
+	rows []eventLogRow,
+	targetMap map[string]eventLogTarget,
+) ([]EventLogView, bool) {
+	result := make([]EventLogView, len(rows))
 	eventDeliveries := make([][]database.Delivery, len(rows))
 
 	var deliveryIDs []string
@@ -1108,7 +1125,7 @@ func (h *Handlers) loadEventsWithDeliveries(
 	eventIDs := make([]string, len(rows))
 
 	for i := range rows {
-		result[i] = rows[i].view()
+		result[i] = rows[i].view(webhookID)
 		eventIDs[i] = rows[i].ID
 
 		webhookDB.Where(
@@ -1130,7 +1147,7 @@ func (h *Handlers) loadEventsWithDeliveries(
 			w, r, "failed to load delivery attempts", err,
 		)
 
-		return nil, 0, false
+		return nil, false
 	}
 
 	resubmits, err := resubmitCounts(webhookDB, eventIDs)
@@ -1139,7 +1156,7 @@ func (h *Handlers) loadEventsWithDeliveries(
 			w, r, "failed to count event resubmissions", err,
 		)
 
-		return nil, 0, false
+		return nil, false
 	}
 
 	for i := range rows {
@@ -1149,7 +1166,7 @@ func (h *Handlers) loadEventsWithDeliveries(
 		result[i].ResubmitCount = resubmits[rows[i].ID]
 	}
 
-	return result, totalEvents, true
+	return result, true
 }
 
 // loadEventLogRows reads one page of the event log projection, newest