refactor: implement pluggable multi-channel architecture

.claude/skills/add-discord/SKILL.md

@@ -12,10 +12,6 @@ Read `.nanoclaw/state.yaml`. If `discord` is in `applied_skills`, skip to Phase
 
 Use `AskUserQuestion` to collect configuration:
 
-AskUserQuestion: Should Discord replace WhatsApp or run alongside it?
-- **Replace WhatsApp** - Discord will be the only channel (sets DISCORD_ONLY=true)
-- **Alongside** - Both Discord and WhatsApp channels active
-
 AskUserQuestion: Do you have a Discord bot token, or do you need to create one?
 
 If they have one, collect it now. If not, we'll create one in Phase 3.
@@ -41,18 +37,14 @@ npx tsx scripts/apply-skill.ts .claude/skills/add-discord
 ```
 
 This deterministically:
-- Adds `src/channels/discord.ts` (DiscordChannel class implementing Channel interface)
+- Adds `src/channels/discord.ts` (DiscordChannel class with self-registration via `registerChannel`)
 - Adds `src/channels/discord.test.ts` (unit tests with discord.js mock)
-- Three-way merges Discord support into `src/index.ts` (multi-channel support, findChannel routing)
-- Three-way merges Discord config into `src/config.ts` (DISCORD_BOT_TOKEN, DISCORD_ONLY exports)
-- Three-way merges updated routing tests into `src/routing.test.ts`
+- Appends `import './discord.js'` to the channel barrel file `src/channels/index.ts`
 - Installs the `discord.js` npm dependency
-- Updates `.env.example` with `DISCORD_BOT_TOKEN` and `DISCORD_ONLY`
 - Records the application in `.nanoclaw/state.yaml`
 
-If the apply reports merge conflicts, read the intent files:
-- `modify/src/index.ts.intent.md` — what changed and invariants for index.ts
-- `modify/src/config.ts.intent.md` — what changed for config.ts
+If the apply reports merge conflicts, read the intent file:
+- `modify/src/channels/index.ts.intent.md` — what changed and invariants
 
 ### Validate code changes
 
@@ -93,16 +85,12 @@ Add to `.env`:
 DISCORD_BOT_TOKEN=<their-token>
 ```
 
-If they chose to replace WhatsApp:
-
-```bash
-DISCORD_ONLY=true
-```
+Channels auto-enable when their credentials are present — no extra configuration needed.
 
 Sync to container environment:
 
 ```bash
-cp .env data/env/env
+mkdir -p data/env && cp .env data/env/env
 ```
 
 The container reads environment from `data/env/env`, not `.env` directly.
@@ -134,15 +122,16 @@ Wait for the user to provide the channel ID (format: `dc:1234567890123456`).
 
 Use the IPC register flow or register directly. The channel ID, name, and folder name are needed.
 
-For a main channel (responds to all messages, uses the `main` folder):
+For a main channel (responds to all messages):
 
 ```typescript
 registerGroup("dc:<channel-id>", {
   name: "<server-name> #<channel-name>",
-  folder: "main",
+  folder: "discord_main",
   trigger: `@${ASSISTANT_NAME}`,
   added_at: new Date().toISOString(),
   requiresTrigger: false,
+  isMain: true,
 });
 ```
 
@@ -151,7 +140,7 @@ For additional channels (trigger-only):
 ```typescript
 registerGroup("dc:<channel-id>", {
   name: "<server-name> #<channel-name>",
-  folder: "<folder-name>",
+  folder: "discord_<channel-name>",
   trigger: `@${ASSISTANT_NAME}`,
   added_at: new Date().toISOString(),
   requiresTrigger: true,

.claude/skills/add-discord/add/src/channels/discord.test.ts

@@ -2,6 +2,12 @@ import { describe, it, expect, beforeEach, vi, afterEach } from 'vitest';
 
 // --- Mocks ---
 
+// Mock registry (registerChannel runs at import time)
+vi.mock('./registry.js', () => ({ registerChannel: vi.fn() }));
+
+// Mock env reader (used by the factory, not needed in unit tests)
+vi.mock('../env.js', () => ({ readEnvFile: vi.fn(() => ({})) }));
+
 // Mock config
 vi.mock('../config.js', () => ({
   ASSISTANT_NAME: 'Andy',
@@ -256,6 +262,8 @@ describe('DiscordChannel', () => {
         'dc:1234567890123456',
         expect.any(String),
         'Test Server #general',
+        'discord',
+        true,
       );
       expect(opts.onMessage).toHaveBeenCalledWith(
         'dc:1234567890123456',
@@ -286,6 +294,8 @@ describe('DiscordChannel', () => {
         'dc:9999999999999999',
         expect.any(String),
         expect.any(String),
+        'discord',
+        true,
       );
       expect(opts.onMessage).not.toHaveBeenCalled();
     });
@@ -365,6 +375,8 @@ describe('DiscordChannel', () => {
         'dc:1234567890123456',
         expect.any(String),
         'Alice',
+        'discord',
+        false,
       );
     });
 
@@ -384,6 +396,8 @@ describe('DiscordChannel', () => {
         'dc:1234567890123456',
         expect.any(String),
         'My Server #bot-chat',
+        'discord',
+        true,
       );
     });
   });

.claude/skills/add-discord/add/src/channels/discord.ts

@@ -1,7 +1,9 @@
 import { Client, Events, GatewayIntentBits, Message, TextChannel } from 'discord.js';
 
 import { ASSISTANT_NAME, TRIGGER_PATTERN } from '../config.js';
+import { readEnvFile } from '../env.js';
 import { logger } from '../logger.js';
+import { registerChannel, ChannelOpts } from './registry.js';
 import {
   Channel,
   OnChatMetadata,
@@ -122,7 +124,8 @@ export class DiscordChannel implements Channel {
       }
 
       // Store chat metadata for discovery
-      this.opts.onChatMetadata(chatJid, timestamp, chatName);
+      const isGroup = message.guild !== null;
+      this.opts.onChatMetadata(chatJid, timestamp, chatName, 'discord', isGroup);
 
       // Only deliver full message for registered groups
       const group = this.opts.registeredGroups()[chatJid];
@@ -234,3 +237,14 @@ export class DiscordChannel implements Channel {
     }
   }
 }
+
+registerChannel('discord', (opts: ChannelOpts) => {
+  const envVars = readEnvFile(['DISCORD_BOT_TOKEN']);
+  const token =
+    process.env.DISCORD_BOT_TOKEN || envVars.DISCORD_BOT_TOKEN || '';
+  if (!token) {
+    logger.warn('Discord: DISCORD_BOT_TOKEN not set');
+    return null;
+  }
+  return new DiscordChannel(token, opts);
+});

.claude/skills/add-discord/manifest.yaml

@@ -6,15 +6,12 @@ adds:
   - src/channels/discord.ts
   - src/channels/discord.test.ts
 modifies:
-  - src/index.ts
-  - src/config.ts
-  - src/routing.test.ts
+  - src/channels/index.ts
 structured:
   npm_dependencies:
     discord.js: "^14.18.0"
   env_additions:
     - DISCORD_BOT_TOKEN
-    - DISCORD_ONLY
 conflicts: []
 depends: []
 test: "npx vitest run src/channels/discord.test.ts"

.claude/skills/add-discord/modify/src/channels/index.ts

@@ -0,0 +1,13 @@
+// Channel self-registration barrel file.
+// Each import triggers the channel module's registerChannel() call.
+
+// discord
+import './discord.js';
+
+// gmail
+
+// slack
+
+// telegram
+
+// whatsapp

.claude/skills/add-discord/modify/src/channels/index.ts.intent.md

@@ -0,0 +1,7 @@
+# Intent: Add Discord channel import
+
+Add `import './discord.js';` to the channel barrel file so the Discord
+module self-registers with the channel registry on startup.
+
+This is an append-only change — existing import lines for other channels
+must be preserved.