fix(frontend): align dm_scope options with backend constants

- Replace "per-channel" with "per-account-channel-peer" (backend supports this)
- Replace "global" with "main" to match backend DMScope constant
- This fixes the mismatch between frontend and backend session scope options

Backend DMScope constants:
- main
- per-peer
- per-channel-peer
- per-account-channel-peer

Previously frontend had:
- per-channel (not recognized by backend)
- per-peer ✓
- per-channel-peer ✓
- global (not recognized by backend, should be "main")

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

web/frontend/src/components/config/form-model.ts

@@ -32,6 +32,13 @@ export interface LauncherForm {
 }
 
 export const DM_SCOPE_OPTIONS = [
+  {
+    value: "per-account-channel-peer",
+    labelKey: "pages.config.session_scope_per_account_channel_peer",
+    labelDefault: "Per Account + Channel + Peer",
+    descKey: "pages.config.session_scope_per_account_channel_peer_desc",
+    descDefault: "Separate context for each user in each channel for each account.",
+  },
   {
     value: "per-channel-peer",
     labelKey: "pages.config.session_scope_per_channel_peer",
@@ -39,13 +46,6 @@ export const DM_SCOPE_OPTIONS = [
     descKey: "pages.config.session_scope_per_channel_peer_desc",
     descDefault: "Separate context for each user in each channel.",
   },
-  {
-    value: "per-channel",
-    labelKey: "pages.config.session_scope_per_channel",
-    labelDefault: "Per Channel",
-    descKey: "pages.config.session_scope_per_channel_desc",
-    descDefault: "One shared context per channel.",
-  },
   {
     value: "per-peer",
     labelKey: "pages.config.session_scope_per_peer",
@@ -54,10 +54,10 @@ export const DM_SCOPE_OPTIONS = [
     descDefault: "One context per user across channels.",
   },
   {
-    value: "global",
+    value: "main",
-    labelKey: "pages.config.session_scope_global",
+    labelKey: "pages.config.session_scope_main",
-    labelDefault: "Global",
+    labelDefault: "Main",
-    descKey: "pages.config.session_scope_global_desc",
+    descKey: "pages.config.session_scope_main_desc",
     descDefault: "All messages share one global context.",
   },
 ] as const