feat: remove container layer, run agents as direct host processes

- Rewrite container-runner.ts to spawn node processes directly instead
  of Docker/Apple Container
- Runner paths configurable via env vars (NANOCLAW_GROUP_DIR, etc.)
  with container-path defaults for backwards compat
- Pass real credentials directly (no credential proxy needed)
- Remove ensureContainerSystemRunning() and startCredentialProxy()
  from startup
- Add build:runners script for building agent-runner and codex-runner
- Fix TS strict mode errors in agent-runner ipc-mcp-stdio.ts

src/channels/discord.test.ts

@@ -161,9 +161,7 @@ function createMessage(overrides: {
     member: overrides.memberDisplayName
       ? { displayName: overrides.memberDisplayName }
       : null,
-    guild: overrides.guildName
-      ? { name: overrides.guildName }
-      : null,
+    guild: overrides.guildName ? { name: overrides.guildName } : null,
     channel: {
       name: overrides.channelName ?? 'general',
       messages: {
@@ -646,8 +644,11 @@ describe('DiscordChannel', () => {
 
       await channel.sendMessage('dc:1234567890123456', 'Hello');
 
-      const fetchedChannel = await currentClient().channels.fetch('1234567890123456');
-      expect(currentClient().channels.fetch).toHaveBeenCalledWith('1234567890123456');
+      const fetchedChannel =
+        await currentClient().channels.fetch('1234567890123456');
+      expect(currentClient().channels.fetch).toHaveBeenCalledWith(
+        '1234567890123456',
+      );
     });
 
     it('strips dc: prefix from JID', async () => {