feat(voice): WhatsApp Cloud Calling — UI [6] (#14346)

## Summary

Frontend for WhatsApp Cloud Calling: header / contact-panel call
buttons, ringing widget, accept/reject/hangup, mute, in-bubble audio
player + transcript, recording-on-hangup upload, mid-call reload
warning. WebRTC is browser-direct to Meta — no media server bridge.

## Closes
- https://linear.app/chatwoot/issue/PLA-150

## How to test

Requires backend support — the controller, services, model changes, and
routes ship in **#14334** (`feature/pla-150`). Merge / deploy that first
(or simultaneously); the FE alone won't function without those
endpoints.

Then on staging, for a WhatsApp Cloud + embedded-signup inbox with the
new \`Configuration → Enable voice calling\` toggle ON and webhook
registered:

1. **Outbound** — open a conversation, click the phone icon in the
conversation header (or contact panel), grant mic, your phone rings,
answer, audio both ways, hang up. Recording + transcript land in the
bubble within ~10s.
2. **Inbound** — call the business number from your phone. The
FloatingCallWidget appears bottom-right with caller name. Click accept,
audio both ways, hang up. Recording + transcript appear.
3. **Mute** — during an active WhatsApp call, click the mic icon next to
hangup. Speech stops reaching Meta until you click again.
4. **Mid-call reload guard** — try `Cmd-R` during an active call;
browser shows a confirm prompt.

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Co-authored-by: iamsivin <iamsivin@gmail.com>
Co-authored-by: Sivin Varghese <64252451+iamsivin@users.noreply.github.com>

app/javascript/dashboard/store/modules/contacts/actions.js

@@ -312,10 +312,14 @@ export const actions = {
     commit(types.CLEAR_CONTACT_FILTERS);
   },
 
-  initiateCall: async ({ commit }, { contactId, inboxId }) => {
+  initiateCall: async ({ commit }, { contactId, inboxId, conversationId }) => {
     commit(types.SET_CONTACT_UI_FLAG, { isInitiatingCall: true });
     try {
-      const response = await ContactAPI.initiateCall(contactId, inboxId);
+      const response = await ContactAPI.initiateCall(
+        contactId,
+        inboxId,
+        conversationId
+      );
       commit(types.SET_CONTACT_UI_FLAG, { isInitiatingCall: false });
       return response.data;
     } catch (error) {

app/javascript/dashboard/store/modules/conversations/actions.js

@@ -329,12 +329,21 @@ const actions = {
       });
       commit(types.ADD_CONVERSATION_ATTACHMENTS, message);
     }
-    handleVoiceCallCreated(message, rootGetters?.getCurrentUserID);
+    handleVoiceCallCreated(
+      message,
+      rootGetters?.getCurrentUserID,
+      rootGetters?.getCurrentUserAvailability
+    );
   },
 
   updateMessage({ commit, rootGetters }, message) {
     commit(types.ADD_MESSAGE, message);
-    handleVoiceCallUpdated(commit, message, rootGetters?.getCurrentUserID);
+    handleVoiceCallUpdated(
+      commit,
+      message,
+      rootGetters?.getCurrentUserID,
+      rootGetters?.getCurrentUserAvailability
+    );
   },
 
   deleteMessage: async function deleteLabels(