chat: OpenCode /chat cwd = general_chat_sessions (match Claude), drop home special-case

Both harnesses now use the resolved chat cwd as their working directory: Claude runs
in it natively, and OpenCode is told the same via its system prompt. Removes the
earlier special-case that pointed OpenCode at the user's home for /chat, so `workingDir`
collapses into `cwd` — which now both tags the session (metadata.officer.cwd) and drives
the Officer system prompt.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/servers/api/chat/websocket.ts

@@ -4,7 +4,7 @@ import type { ClientMessage, ServerMessage, Message, ChatEvent } from './types';
 import { sessionManager } from './session-manager';
 import { sendClaudeCodeStreaming } from '@@/channels/send-claude-code';
 import { sendOpenCodeStreaming } from '@@/channels/send-opencode';
-import { ensureGeneralChatSessionsCwd, getGeneralChatSessionsCwd } from './claude-sessions';
+import { ensureGeneralChatSessionsCwd } from './claude-sessions';
 import * as sidecar from '@@/sidecar-registry';
 import { join } from 'path';
 import { getHomeDirForRole, getEmailAccountsDir } from '../../../servers/data-path';
@@ -459,10 +459,6 @@ async function handleOpenCodeChat(
 
   const onEvent = createEventHandler(sessionId, model, cwd);
 
-  // The dir the OpenCode model should treat as its cwd (via the Officer system prompt). For the general
-  // /chat, the resolved cwd is just the general_chat_sessions grouping placeholder, so use the user's home.
-  const workingDir = cwd === getGeneralChatSessionsCwd(email) ? getHomeDirForRole(email, ws.data.role) : cwd;
-
   try {
     const handle = await sendOpenCodeStreaming({
       userId,
@@ -471,7 +467,6 @@ async function handleOpenCodeChat(
       prompt: effectivePrompt,
       sessionKey: sessionId,
       cwd,
-      workingDir,
       model,
       role: ws.data.role,
       resumeSessionId: msg.resumeSessionId,