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

The receiver keeps the query string of the request it received on the event, 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 with the request, the event log leaving out one over 32 KiB as it does request headers. The archive and log targets carry it. An HTTP target gets a `forwardQuery` setting, off by default, on both target forms and in the target list: on, each delivery, replays and resubmits included, appends the query string to the target URL, joined with `&` to one it already has.

Model: opus-5-5

internal/delivery/target_log.go

@@ -9,9 +9,9 @@ import (
 )
 
 // logTarget is a fire-and-forget target that logs the entire
-// inbound webhook — the full request body and headers, plus
-// the method, content type, and the webhook and entrypoint
-// ids — then records a single successful attempt.
+// inbound webhook — the full request body, query string and
+// headers, plus the method, content type, and the webhook and
+// entrypoint ids — then records a single successful attempt.
 //
 // This is the one log call in the service that deliberately writes
 // unbounded client-chosen bytes, so it is the one exception to the
@@ -46,6 +46,7 @@ func (t *logTarget) Deliver(
 		"webhook_id", d.Event.WebhookID,
 		"entrypoint_id", d.Event.EntrypointID,
 		"method", d.Event.Method,
+		"raw_query", d.Event.RawQuery,
 		"content_type", d.Event.ContentType,
 		"headers", d.Event.Headers,
 		"body", d.Event.Body,