Merge upstream v2.40.0 with local fork additions preserved

Incorporates 163 upstream commits (origin/main) while preserving all
local skills, agents, and commands. Metadata descriptions updated to
reflect actual component counts (30 agents, 56 skills, 7 commands).
file-todos/SKILL.md merged with both upstream command rename and local
assessment fields.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

plugins/compound-engineering/skills/excalidraw-png-export/scripts/setup.sh

@@ -0,0 +1,37 @@
+#!/bin/bash
+# First-time setup for excalidraw-png-export skill.
+# Installs playwright and chromium headless into a dedicated directory.
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+EXPORT_DIR="$SCRIPT_DIR/.export-runtime"
+
+if [ -d "$EXPORT_DIR/node_modules/playwright" ]; then
+  echo "Runtime already installed at $EXPORT_DIR"
+  exit 0
+fi
+
+echo "Installing excalidraw-png-export runtime..."
+mkdir -p "$EXPORT_DIR"
+cd "$EXPORT_DIR"
+
+# Initialize package.json with ESM support
+cat > package.json << 'PACKAGEEOF'
+{
+  "name": "excalidraw-export-runtime",
+  "version": "1.0.0",
+  "type": "module",
+  "private": true
+}
+PACKAGEEOF
+
+npm install playwright 2>&1
+npx playwright install chromium 2>&1
+
+# canvas provides accurate text measurement for convert.mjs.
+# Requires Cairo native library: brew install pkg-config cairo pango libpng jpeg giflib librsvg
+# Falls back to heuristic sizing if unavailable.
+npm install canvas 2>&1 || echo "WARN: canvas install failed (missing Cairo?). Heuristic text sizing will be used."
+
+echo "Setup complete. Runtime installed at $EXPORT_DIR"