feat(captain): toggle assistant audience between everyone and specific

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app/javascript/dashboard/i18n/locale/en/integrations.json

@@ -528,10 +528,18 @@
           "ALLOW_CONTACT_ATTRIBUTES": "Allow access to contact information"
         },
         "AUDIENCE": {
+          "EVERYONE": {
+            "LABEL": "Everyone",
+            "DESC": "Captain responds to every conversation in connected inboxes."
+          },
+          "SPECIFIC": {
+            "LABEL": "Specific audience",
+            "DESC": "Captain responds only to customers who match the conditions below."
+          },
           "ADD_CONDITION": "Add condition",
           "ADD_GROUP": "Add condition group",
           "EMPTY_TITLE": "No conditions yet",
-          "EMPTY_BODY": "By default, Captain responds to every conversation in connected inboxes. Add a condition to target specific customers, or a condition group to combine conditions with different and/or logic.",
+          "EMPTY_BODY": "Add a condition to target specific customers, or a condition group to combine conditions with different and/or logic.",
           "MATCH_PREFIX": "Match",
           "MATCH_SUFFIX": "of the following",
           "MATCH_ALL": "all",
@@ -579,7 +587,7 @@
         },
         "AUDIENCE": {
           "TITLE": "Audience",
-          "DESCRIPTION": "Limit which customers this assistant responds to. Leave empty to respond to everyone."
+          "DESCRIPTION": "Choose whether this assistant responds to everyone or only to a specific audience."
         },
         "SCHEDULE": {
           "TITLE": "Schedule",