feat(session): add dmScope for multi-user DM isolation

Co-authored-by: Alphonse-arianee <Alphonse-arianee@users.noreply.github.com>

src/config/schema.ts

@@ -167,6 +167,7 @@ const FIELD_LABELS: Record<string, string> = {
   "commands.useAccessGroups": "Use Access Groups",
   "ui.seamColor": "Accent Color",
   "browser.controlUrl": "Browser Control URL",
+  "session.dmScope": "DM Session Scope",
   "session.agentToAgent.maxPingPongTurns": "Agent-to-Agent Ping-Pong Turns",
   "messages.ackReaction": "Ack Reaction Emoji",
   "messages.ackReactionScope": "Ack Reaction Scope",
@@ -311,6 +312,8 @@ const FIELD_HELP: Record<string, string> = {
   "commands.debug": "Allow /debug chat command for runtime-only overrides (default: false).",
   "commands.restart": "Allow /restart and gateway restart tool actions (default: false).",
   "commands.useAccessGroups": "Enforce access-group allowlists/policies for commands.",
+  "session.dmScope":
+    'DM session scoping: "main" keeps continuity; "per-peer" or "per-channel-peer" isolates DM history (recommended for shared inboxes).',
   "channels.telegram.configWrites":
     "Allow Telegram to write config in response to channel events/commands (default: true).",
   "channels.slack.configWrites":

src/config/types.base.ts

@@ -1,6 +1,7 @@
 export type ReplyMode = "text" | "command";
 export type TypingMode = "never" | "instant" | "thinking" | "message";
 export type SessionScope = "per-sender" | "global";
+export type DmScope = "main" | "per-peer" | "per-channel-peer";
 export type ReplyToMode = "off" | "first" | "all";
 export type GroupPolicy = "open" | "disabled" | "allowlist";
 export type DmPolicy = "pairing" | "allowlist" | "open" | "disabled";
@@ -54,6 +55,8 @@ export type SessionSendPolicyConfig = {
 
 export type SessionConfig = {
   scope?: SessionScope;
+  /** DM session scoping (default: "main"). */
+  dmScope?: DmScope;
   resetTriggers?: string[];
   idleMinutes?: number;
   heartbeatIdleMinutes?: number;

src/config/zod-schema.session.ts

@@ -10,6 +10,11 @@ import {
 export const SessionSchema = z
   .object({
     scope: z.union([z.literal("per-sender"), z.literal("global")]).optional(),
+    dmScope: z.union([
+      z.literal("main"),
+      z.literal("per-peer"),
+      z.literal("per-channel-peer"),
+    ]).optional(),
     resetTriggers: z.array(z.string()).optional(),
     idleMinutes: z.number().int().positive().optional(),
     heartbeatIdleMinutes: z.number().int().positive().optional(),