v5.0: fix TRANSCRIPT_DIR default, disable custom post type

Root cause: TRANSCRIPT_DIR was /home/node/.openclaw/agents but the actual
sessions live at /root/.openclaw/agents. The daemon started, watched an empty
directory, and never detected any sessions.

Changes:
- config.js: default TRANSCRIPT_DIR -> /root/.openclaw/agents
- start-daemon.sh: same fix for fallback default
- .env.daemon (local): TRANSCRIPT_DIR fixed, PLUGIN_ENABLED=false

The custom_livestatus post type requires the Mattermost plugin webapp React
bundle to render. Disabled by default — now uses plain REST API posts with
markdown formatting, which render reliably everywhere (desktop, mobile, web).

Previous version preserved as git tag v4.1.

start-daemon.sh

@@ -22,7 +22,7 @@ fi
 export MM_BOT_TOKEN="${MM_BOT_TOKEN:?MM_BOT_TOKEN is required}"
 export MM_BASE_URL="${MM_BASE_URL:-https://slack.solio.tech}"
 export MM_BOT_USER_ID="${MM_BOT_USER_ID:-eqtkymoej7rw7dp8xbh7hywzrr}"
-export TRANSCRIPT_DIR="${TRANSCRIPT_DIR:-/home/node/.openclaw/agents}"
+export TRANSCRIPT_DIR="${TRANSCRIPT_DIR:-/root/.openclaw/agents}"
 export LOG_LEVEL="${LOG_LEVEL:-info}"
 export IDLE_TIMEOUT_S="${IDLE_TIMEOUT_S:-60}"
 export SESSION_POLL_MS="${SESSION_POLL_MS:-2000}"