Refactor visual brainstorming: browser displays, terminal commands (#509)

* Refactor visual brainstorming: browser displays, terminal commands

Replaces the blocking TaskOutput/wait-for-feedback.sh pattern with a
non-blocking model where the browser is an interactive display and the
terminal stays available for conversation.

Server changes:
- Write user click events to .events JSONL file (per-screen, cleared on
  new screen push) so Claude reads them on its next turn
- Replace regex-based wrapInFrame with <!-- CONTENT --> placeholder
- Add --foreground flag to start-server.sh for sandbox environments
- Harden startup with nohup/disown and liveness check

UI changes:
- Remove feedback footer (textarea + Send button)
- Add selection indicator bar ("Option X selected — return to terminal")
- Narrow click handler to [data-choice] elements only

Skill changes:
- Rewrite visual-companion.md for non-blocking loop
- Fix visual companion being skipped on Codex (no browser tools needed)
- Make visual companion offer a standalone question (one question rule)

Deletes wait-for-feedback.sh entirely.

* Add visual companion offer to brainstorming checklist for UX topics

The visual companion was a disconnected section at the bottom of SKILL.md
that agents never reached because it wasn't in the mandatory checklist.
Now step 2 evaluates whether the topic involves visual/UX decisions and
offers the companion if so. Non-visual topics (APIs, data models, etc.)
skip the step entirely.

* Add multi-select support to visual companion

Containers with data-multiselect allow toggling multiple selections.
Without it, behavior is unchanged (single-select). Indicator bar shows
count when multiple items are selected.

lib/brainstorm-server/start-server.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 # Start the brainstorm server and output connection info
-# Usage: start-server.sh [--project-dir <path>]
+# Usage: start-server.sh [--project-dir <path>] [--host <bind-host>] [--url-host <display-host>] [--foreground] [--background]
 #
 # Starts server on a random high port, outputs JSON with URL.
 # Each session gets its own directory to avoid conflicts.
@@ -8,17 +8,42 @@
 # Options:
 #   --project-dir <path>  Store session files under <path>/.superpowers/brainstorm/
 #                         instead of /tmp. Files persist after server stops.
+#   --host <bind-host>    Host/interface to bind (default: 127.0.0.1).
+#                         Use 0.0.0.0 in remote/containerized environments.
+#   --url-host <host>     Hostname shown in returned URL JSON.
+#   --foreground          Run server in the current terminal (no backgrounding).
+#   --background          Force background mode (overrides Codex auto-foreground).
 
 SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
 
 # Parse arguments
 PROJECT_DIR=""
+FOREGROUND="false"
+FORCE_BACKGROUND="false"
+BIND_HOST="127.0.0.1"
+URL_HOST=""
 while [[ $# -gt 0 ]]; do
   case "$1" in
     --project-dir)
       PROJECT_DIR="$2"
       shift 2
       ;;
+    --host)
+      BIND_HOST="$2"
+      shift 2
+      ;;
+    --url-host)
+      URL_HOST="$2"
+      shift 2
+      ;;
+    --foreground|--no-daemon)
+      FOREGROUND="true"
+      shift
+      ;;
+    --background|--daemon)
+      FORCE_BACKGROUND="true"
+      shift
+      ;;
     *)
       echo "{\"error\": \"Unknown argument: $1\"}"
       exit 1
@@ -26,6 +51,19 @@ while [[ $# -gt 0 ]]; do
   esac
 done
 
+if [[ -z "$URL_HOST" ]]; then
+  if [[ "$BIND_HOST" == "127.0.0.1" || "$BIND_HOST" == "localhost" ]]; then
+    URL_HOST="localhost"
+  else
+    URL_HOST="$BIND_HOST"
+  fi
+fi
+
+# Codex environments may reap detached/background processes. Prefer foreground by default.
+if [[ -n "${CODEX_CI:-}" && "$FOREGROUND" != "true" && "$FORCE_BACKGROUND" != "true" ]]; then
+  FOREGROUND="true"
+fi
+
 # Generate unique session directory
 SESSION_ID="$$-$(date +%s)"
 
@@ -48,15 +86,38 @@ if [[ -f "$PID_FILE" ]]; then
   rm -f "$PID_FILE"
 fi
 
-# Start server, capturing output to log file
 cd "$SCRIPT_DIR"
-BRAINSTORM_DIR="$SCREEN_DIR" node index.js > "$LOG_FILE" 2>&1 &
+
+# Foreground mode for environments that reap detached/background processes.
+if [[ "$FOREGROUND" == "true" ]]; then
+  echo "$$" > "$PID_FILE"
+  env BRAINSTORM_DIR="$SCREEN_DIR" BRAINSTORM_HOST="$BIND_HOST" BRAINSTORM_URL_HOST="$URL_HOST" node index.js
+  exit $?
+fi
+
+# Start server, capturing output to log file
+# Use nohup to survive shell exit; disown to remove from job table
+nohup env BRAINSTORM_DIR="$SCREEN_DIR" BRAINSTORM_HOST="$BIND_HOST" BRAINSTORM_URL_HOST="$URL_HOST" node index.js > "$LOG_FILE" 2>&1 &
 SERVER_PID=$!
+disown "$SERVER_PID" 2>/dev/null
 echo "$SERVER_PID" > "$PID_FILE"
 
 # Wait for server-started message (check log file)
 for i in {1..50}; do
   if grep -q "server-started" "$LOG_FILE" 2>/dev/null; then
+    # Verify server is still alive after a short window (catches process reapers)
+    alive="true"
+    for _ in {1..20}; do
+      if ! kill -0 "$SERVER_PID" 2>/dev/null; then
+        alive="false"
+        break
+      fi
+      sleep 0.1
+    done
+    if [[ "$alive" != "true" ]]; then
+      echo "{\"error\": \"Server started but was killed. Retry in a persistent terminal with: $SCRIPT_DIR/start-server.sh${PROJECT_DIR:+ --project-dir $PROJECT_DIR} --host $BIND_HOST --url-host $URL_HOST --foreground\"}"
+      exit 1
+    fi
     grep "server-started" "$LOG_FILE" | head -1
     exit 0
   fi