fix(action_cable): accept both /user/123 and /user_123 channel formats

- Benjamin standardized on /user_123 in mozo.rb (underscore, no slash)
- Old remap regex ^/user/(.+)$ didn't match /user_123
- Fix: ^/user[/_](.+)$ accepts both separators → user_123

lib/mozo/broadcaster/action_cable.rb

@@ -11,9 +11,9 @@ module Mozo
     #   - Integrated with Rails authentication (cookies, sessions)
     #   - WebSocket native (no long-polling fallback needed with modern browsers)
     #
-    # Channel naming is kept compatible with the existing Faye convention:
-    #   /user/:uid    → user_<uid>
-    #   /supplier/:sid → supplier_<sid>
+    # Channel naming: accepts both Faye format and underscore format:
+    #   /user/123 or /user_123  →  user_123
+    #   /supplier/456  or /supplier_456  →  supplier_456
     #
     # To use:
     #   Set Mozo.broadcaster = Mozo::Broadcaster::ActionCable.new
@@ -21,8 +21,8 @@ module Mozo
     #
     class ActionCable
       CHANNEL_PREFIX_REMAP = {
-        %r{^/user/(.+)$}     => 'user_\1',
-        %r{^/supplier/(.+)$} => 'supplier_\1'
+        %r{^/user[/_](.+)$}     => 'user_\1',
+        %r{^/supplier[/_](.+)$} => 'supplier_\1'
       }.freeze
 
       def broadcast(message)