feat(whatsapp): add reply-based activation modes for groups

This commit adds more granular control over group activation with new modes:

- 'replies': Bot only responds when someone replies to one of its messages
- 'mention+replies': Bot responds to @mentions OR replies (most flexible)
- 'never': Bot never responds except for control commands from owners

The existing 'mention' (default) and 'always' modes remain unchanged.

**Implementation details:**
- Added new GroupActivationMode types: 'replies', 'mention+replies', 'never'
- Enhanced group-gating logic to detect replies to bot messages
- Updated all command help messages and documentation
- Reply detection uses both JID and E.164 matching for reliability

**Use cases:**
- 'replies': Reduces noise in busy groups, bot only joins when explicitly engaged
- 'mention+replies': Allows natural conversation flow after initial @mention
- 'never': Temporarily disable bot in a group without removing it

Closes: N/A (feature request)

docs/channels/whatsapp.md

@@ -200,7 +200,10 @@ The wizard uses it to set your **allowlist/owner** so your own DMs are permitted
 - Activation modes:
   - `mention` (default): requires @mention or regex match.
   - `always`: always triggers.
-- `/activation mention|always` is owner-only and must be sent as a standalone message.
+  - `replies`: only triggers when someone replies to a bot message.
+  - `mention+replies`: triggers on @mention/regex match OR replies to bot messages.
+  - `never`: never triggers (except for control commands from owners).
+- `/activation mention|always|replies|mention+replies|never` is owner-only and must be sent as a standalone message.
 - Owner = `channels.whatsapp.allowFrom` (or self E.164 if unset).
 - **History injection** (pending-only):
   - Recent *unprocessed* messages (default 50) inserted under:

src/acp/commands.ts

@@ -21,7 +21,7 @@ export function getAvailableCommands(): AvailableCommand[] {
     { name: "dock-telegram", description: "Route replies to Telegram." },
     { name: "dock-discord", description: "Route replies to Discord." },
     { name: "dock-slack", description: "Route replies to Slack." },
-    { name: "activation", description: "Set group activation (mention|always)." },
+    { name: "activation", description: "Set group activation (mention|always|replies|mention+replies|never)." },
     { name: "send", description: "Set send mode (on|off|inherit)." },
     { name: "reset", description: "Reset the session (/new)." },
     { name: "new", description: "Reset the session (/reset)." },

src/auto-reply/group-activation.ts

@@ -1,11 +1,14 @@
 import { normalizeCommandBody } from "./commands-registry.js";
 
-export type GroupActivationMode = "mention" | "always";
+export type GroupActivationMode = "mention" | "always" | "replies" | "mention+replies" | "never";
 
 export function normalizeGroupActivation(raw?: string | null): GroupActivationMode | undefined {
   const value = raw?.trim().toLowerCase();
   if (value === "mention") return "mention";
   if (value === "always") return "always";
+  if (value === "replies") return "replies";
+  if (value === "mention+replies") return "mention+replies";
+  if (value === "never") return "never";
   return undefined;
 }
 

src/auto-reply/reply/commands-session.ts

@@ -66,7 +66,7 @@ export const handleActivationCommand: CommandHandler = async (params, allowTextC
   if (!activationCommand.mode) {
     return {
       shouldContinue: false,
-      reply: { text: "⚙️ Usage: /activation mention|always" },
+      reply: { text: "⚙️ Usage: /activation mention|always|replies|mention+replies|never" },
     };
   }
   if (params.sessionEntry && params.sessionStore && params.sessionKey) {

src/tui/commands.ts

@@ -150,7 +150,7 @@ export function helpText(options: SlashCommandOptions = {}): string {
     "/usage <off|tokens|full>",
     "/elevated <on|off|ask|full>",
     "/elev <on|off|ask|full>",
-    "/activation <mention|always>",
+    "/activation <mention|always|replies|mention+replies|never>",
     "/new or /reset",
     "/abort",
     "/settings",

src/tui/tui-command-handlers.ts

@@ -391,7 +391,7 @@ export function createCommandHandlers(context: CommandHandlerContext) {
         break;
       case "activation":
         if (!args) {
-          chatLog.addSystem("usage: /activation <mention|always>");
+          chatLog.addSystem("usage: /activation <mention|always|replies|mention+replies|never>");
           break;
         }
         try {

src/web/auto-reply/monitor/group-gating.ts

@@ -101,26 +101,40 @@ export function applyGroupGating(params: {
     sessionKey: params.sessionKey,
     conversationId: params.conversationId,
   });
-  const requireMention = activation !== "always";
+  
+  // Check if this message is a reply to the bot
   const selfJid = params.msg.selfJid?.replace(/:\\d+/, "");
   const replySenderJid = params.msg.replyToSenderJid?.replace(/:\\d+/, "");
   const selfE164 = params.msg.selfE164 ? normalizeE164(params.msg.selfE164) : null;
   const replySenderE164 = params.msg.replyToSenderE164
     ? normalizeE164(params.msg.replyToSenderE164)
     : null;
-  const implicitMention = Boolean(
+  const isReplyToBot = Boolean(
     (selfJid && replySenderJid && selfJid === replySenderJid) ||
     (selfE164 && replySenderE164 && selfE164 === replySenderE164),
   );
+  
+  // Determine if we should process based on activation mode
+  const shouldProcess = (() => {
+    if (activation === "always") return true;
+    if (activation === "never") return shouldBypassMention;
+    if (activation === "replies") return isReplyToBot || shouldBypassMention;
+    if (activation === "mention+replies") return wasMentioned || isReplyToBot || shouldBypassMention;
+    // Default to "mention" mode
+    return wasMentioned || shouldBypassMention;
+  })();
+  
+  const requireMention = activation !== "always" && activation !== "replies";
   const mentionGate = resolveMentionGating({
     requireMention,
     canDetectMention: true,
     wasMentioned,
-    implicitMention,
+    implicitMention: isReplyToBot,
     shouldBypassMention,
   });
   params.msg.wasMentioned = mentionGate.effectiveWasMentioned;
-  if (!shouldBypassMention && requireMention && mentionGate.shouldSkip) {
+  
+  if (!shouldProcess) {
     params.logVerbose(
       `Group message stored for context (no mention detected) in ${params.conversationId}: ${params.msg.body}`,
     );