Move webhook pages to /hook/ID and inbound URLs to /h/UUID (closes #367)

The webhook page and everything under it move from /source/ID to /hook/ID; the list and new-webhook form from /sources to /hooks and /hooks/new; the event log from .../logs to /hook/ID/events; entrypoint URLs, the ones senders post to, from /webhook/UUID to /h/UUID. The old paths are simply gone, per the owner's ruling. Every link, redirect, form action, test, comment and README mention follows; every link to the event log, and its title and heading, read "Full Event Log".

Keeping the UUID out of logs, metrics labels and error reports, and the receiver rate limits, key on the route itself, so they cover /h/ unchanged. Routed tests follow every link and form the pages render to a moved page.

Model: opus-5-5

internal/middleware/metrics_test.go

@@ -28,7 +28,7 @@ const (
 
 	// receiverRoutePattern is the one handler label every receiver
 	// request must produce, however the client varies the path.
-	receiverRoutePattern = "/webhook/{uuid}"
+	receiverRoutePattern = "/h/{uuid}"
 
 	// okRoute is a static route used to pin that the response-writer
 	// interceptor still reports status and size after the handler id
@@ -143,13 +143,13 @@ func drivePaths(
 	return drive(t, h, probes)
 }
 
-// receiverPaths returns n distinct /webhook/ paths, each naming a
+// receiverPaths returns n distinct /h/ paths, each naming a
 // fresh UUID exactly as an unauthenticated flood would.
 func receiverPaths(n int) []string {
 	paths := make([]string, 0, n)
 
 	for range n {
-		paths = append(paths, "/webhook/"+uuid.NewString())
+		paths = append(paths, "/h/"+uuid.NewString())
 	}
 
 	return paths
@@ -220,7 +220,7 @@ func keys(set map[string]struct{}) []string {
 
 // TestMetrics_DistinctReceiverPathsMintOneLabelSet is the direct
 // assertion the issue asks for: N requests to N distinct
-// /webhook/<uuid> paths must produce exactly ONE handler label, the
+// /h/<uuid> paths must produce exactly ONE handler label, the
 // route pattern. Before the fix this produced N of them.
 func TestMetrics_DistinctReceiverPathsMintOneLabelSet(t *testing.T) {
 	t.Parallel()
@@ -250,7 +250,7 @@ func TestMetrics_DistinctReceiverPathsMintOneLabelSet(t *testing.T) {
 	// The scrape must not republish the UUIDs it was driven with.
 	// They are the receiver's only credential.
 	for _, p := range paths {
-		id := strings.TrimPrefix(p, "/webhook/")
+		id := strings.TrimPrefix(p, "/h/")
 		for label := range labels {
 			assert.NotContains(
 				t, label, id,
@@ -354,7 +354,7 @@ func TestMetrics_UnmatchedPathsCollapseToTheSentinel(t *testing.T) {
 		if i%2 == 0 {
 			paths = append(paths, "/"+id)
 		} else {
-			paths = append(paths, "/webhook/"+id+"/"+id)
+			paths = append(paths, "/h/"+id+"/"+id)
 		}
 	}