Add webhook name field to improve webhook identification (#37025) (#37040)

Add an optional Name field to webhooks so users can give them
human-readable labels instead of relying only on URLs. The webhook
overview page now displays names when available, or falls back to the
URL for unnamed webhooks.

Fixes #37025

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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

models/webhook/webhook.go

@@ -126,6 +126,7 @@ type Webhook struct {
 	OwnerID                   int64 `xorm:"INDEX"`
 	IsSystemWebhook           bool
 	URL                       string `xorm:"url TEXT"`
+	Name                      string `xorm:"VARCHAR(255) NOT NULL DEFAULT ''"`
 	HTTPMethod                string `xorm:"http_method"`
 	ContentType               HookContentType
 	Secret                    string `xorm:"TEXT"`