feat(webhooks): add name to webhook (#12641)

## Description

When working with webhooks, it's easy to lose track of which URL is
which. Adding a `name` (optional) column to the webhook model is a
straight-forward solution to make it significantly easier to identify
webhooks.

## Type of change

- [x] New feature (non-breaking change which adds functionality)

## How Has This Been Tested?

Model and controller specs, and also running in production over several
months without any issues.

| Before | After |
| --- | --- |
| <img width="949" height="990" alt="image copy 3"
src="https://github.com/user-attachments/assets/6b33c072-7d16-4a9c-a129-f9c0751299f5"
/> | <img width="806" height="941" alt="image"
src="https://github.com/user-attachments/assets/77f3cb3a-2eb0-41ac-95bf-d02915589690"
/> |
| <img width="1231" height="650" alt="image copy 2"
src="https://github.com/user-attachments/assets/583374af-96e0-4436-b026-4ce79b7f9321"
/> | <img width="1252" height="650" alt="image copy"
src="https://github.com/user-attachments/assets/aa81fb31-fd18-4e21-a40e-d8ab0dc76b4e"
/> |


## Checklist:

- [x] My code follows the style guidelines of this project
- [x] I have performed a self-review of my code
- [x] I have commented on my code, particularly in hard-to-understand
areas
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] New and existing unit tests pass locally with my changes
- [x] Any dependent changes have been merged and published in downstream
modules

db/migrate/20251010143218_add_name_to_webhooks.rb

@@ -0,0 +1,5 @@
+class AddNameToWebhooks < ActiveRecord::Migration[7.1]
+  def change
+    add_column :webhooks, :name, :string, null: true
+  end
+end

db/schema.rb

@@ -1230,6 +1230,7 @@ ActiveRecord::Schema[7.1].define(version: 2025_10_22_152158) do
     t.datetime "updated_at", null: false
     t.integer "webhook_type", default: 0
     t.jsonb "subscriptions", default: ["conversation_status_changed", "conversation_updated", "conversation_created", "contact_created", "contact_updated", "message_created", "message_updated", "webwidget_triggered"]
+    t.string "name"
     t.index ["account_id", "url"], name: "index_webhooks_on_account_id_and_url", unique: true
   end