Remove an http target's max_queue_size (closes #477)

Nothing in delivery ever read it, so setting it bounded nothing. The
field, the "Max Queue Size" line in the target list, its README row and
the tests that set or checked it are gone. An existing database keeps
its old column, which is no longer read.

Model: opus-5-5

internal/database/model_target.go

@@ -31,8 +31,7 @@ type Target struct {
 
 	// For HTTP targets (max_retries=0 means fire-and-forget,
 	// >0 enables retries with backoff)
-	MaxRetries   int `json:"maxRetries,omitempty"`
-	MaxQueueSize int `json:"maxQueueSize,omitempty"`
+	MaxRetries int `json:"maxRetries,omitempty"`
 
 	// Relations. No model marshals the record it belongs to:
 	// Webhook.Targets leads back here, and the JSON could loop.

internal/delivery/target_config_view.go

@@ -173,13 +173,6 @@ func httpConfigFields(t *database.Target) []ConfigField {
 
 	fields = append(fields, maxRetriesField(t))
 
-	if t.MaxQueueSize > 0 {
-		fields = append(fields, ConfigField{
-			Label: "Max Queue Size",
-			Value: strconv.Itoa(t.MaxQueueSize),
-		})
-	}
-
 	return fields
 }
 

internal/delivery/target_config_view_test.go

@@ -197,14 +197,12 @@ func TestNewTargetViews_Slack(t *testing.T) {
 }
 
 // TestNewTargetViews_SlackRetries proves a Slack target shows
-// its retry count the same way an HTTP target does, and no
-// queue size even when one is stored: delivery never reads it.
+// its retry count the same way an HTTP target does.
 func TestNewTargetViews_SlackRetries(t *testing.T) {
 	t.Parallel()
 
 	target := slackTarget()
 	target.MaxRetries = 2
-	target.MaxQueueSize = 100
 
 	view := viewFor(t, target)
 
@@ -226,8 +224,7 @@ func TestNewTargetViews_HTTP(t *testing.T) {
 		Config: `{"url":"` + viewExampleHook + `",` +
 			`"timeout":30,` +
 			`"headers":{"Authorization":"Bearer sekrit"}}`,
-		MaxRetries:   5,
-		MaxQueueSize: 100,
+		MaxRetries: 5,
 	})
 
 	fields := fieldMap(view.Config)
@@ -239,7 +236,6 @@ func TestNewTargetViews_HTTP(t *testing.T) {
 			"Timeout":         "30s",
 			"Headers":         "1 configured",
 			viewMaxRetries:    "5",
-			"Max Queue Size":  "100",
 		},
 		fields,
 	)