feat: add debugging infrastructure and CLAUDE.md optimization

- Add docs/DEBUGGING-CHECKLIST.md with systematic troubleshooting guide
- Enhance SessionStart hooks to detect missing MCP venvs and warn users
- Add Installation Paths and Debugging sections to CLAUDE.md
- Add Plugin Commands by Category table to Quick Start
- Condense Versioning section for better readability
- Add scripts/check-venv.sh for programmatic venv checking
- Update docs/CANONICAL-PATHS.md with new files

Addresses issues #97, #98, #99

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

scripts/check-venv.sh

@@ -0,0 +1,37 @@
+#!/usr/bin/env bash
+#
+# check-venv.sh - Check if MCP server venvs exist in installed marketplace
+#
+# Usage: ./scripts/check-venv.sh
+#
+# Exit codes:
+#   0 - All venvs exist (or not installed via marketplace)
+#   1 - Venvs missing, needs setup
+#
+# This script is designed to be called from SessionStart hooks
+# to enable self-healing MCP server setup.
+
+set -euo pipefail
+
+# Installed marketplace location
+MKTPLACE="$HOME/.claude/plugins/marketplaces/leo-claude-mktplace"
+
+# If not installed via marketplace, exit silently
+if [[ ! -d "$MKTPLACE" ]]; then
+    exit 0
+fi
+
+# Check if gitea venv exists
+if [[ ! -f "$MKTPLACE/mcp-servers/gitea/.venv/bin/python" ]]; then
+    echo "SETUP_NEEDED"
+    exit 1
+fi
+
+# Check if netbox venv exists
+if [[ ! -f "$MKTPLACE/mcp-servers/netbox/.venv/bin/python" ]]; then
+    echo "SETUP_NEEDED"
+    exit 1
+fi
+
+# All good
+exit 0