Store and show an event's query string, and pass it on to an HTTP target when set (closes #312)

The receiver dropped the query string of every request it received, so a sender's URL parameters were silently lost. Each event now keeps it, as sent, in a new `raw_query` column of the per-webhook `events` table; a resubmitted copy carries its original's. The event log and the event's page show it in the shared request block, the event log leaving out one over 32 KiB with a link, as for headers. The archive and log targets carry it. HTTP targets gain "Pass the query string on to this target", off by default: on, deliveries, replays and resubmits append it to the target URL, joined with `&` to one already there. The access log still hides it.

Model: opus-5-5

internal/handlers/webhook.go

@@ -230,6 +230,7 @@ type eventSource struct {
 	WebhookID    string
 	EntrypointID string
 	Method       string
+	RawQuery     string
 	HeadersJSON  string
 	ContentType  string
 	Body         []byte
@@ -245,6 +246,7 @@ func (s eventSource) event() *database.Event {
 		WebhookID:         s.WebhookID,
 		EntrypointID:      s.EntrypointID,
 		Method:            s.Method,
+		RawQuery:          s.RawQuery,
 		Headers:           s.HeadersJSON,
 		Body:              string(s.Body),
 		BodyBytes:         int64(len(s.Body)),
@@ -264,6 +266,7 @@ func requestEventSource(
 		WebhookID:    entrypoint.WebhookID,
 		EntrypointID: entrypoint.ID,
 		Method:       r.Method,
+		RawQuery:     r.URL.RawQuery,
 		HeadersJSON:  string(headersJSON),
 		ContentType:  r.Header.Get("Content-Type"),
 		Body:         body,
@@ -441,6 +444,7 @@ func buildDeliveryTasks(
 			TargetConfig: targets[i].Config,
 			MaxRetries:   targets[i].MaxRetries,
 			Method:       event.Method,
+			RawQuery:     event.RawQuery,
 			Headers:      event.Headers,
 			ContentType:  event.ContentType,
 			Body:         bodyPtr,