feat: ArcheFlow — multi-agent orchestration plugin for Claude Code

Zero-dependency Claude Code plugin using Jungian archetypes as
behavioral protocols for multi-agent orchestration.

- 7 archetypes (Explorer, Creator, Maker, Guardian, Skeptic, Trickster, Sage)
- ArcheHelix: rising PDCA quality spiral with feedback loops
- Shadow detection: automatic dysfunction recognition and correction
- 3 built-in workflows (fast, standard, thorough)
- Autonomous mode: unattended overnight sessions with full visibility
- Custom archetypes and workflows via markdown/YAML
- SessionStart hook for automatic bootstrap
- Examples for feature implementation and security review

hooks/session-start

@@ -0,0 +1,29 @@
+#!/usr/bin/env bash
+# SessionStart hook for ArcheFlow plugin.
+# Injects the using-archeflow skill as additional context.
+
+set -euo pipefail
+
+PLUGIN_ROOT="$(cd "$(dirname "$0")/.." && pwd)"
+SKILL_FILE="${PLUGIN_ROOT}/skills/using-archeflow/SKILL.md"
+
+if [ ! -f "$SKILL_FILE" ]; then
+  echo '{}'
+  exit 0
+fi
+
+CONTENT=$(awk 'BEGIN{skip=0} /^---$/{skip++; next} skip>=2{print}' "$SKILL_FILE")
+
+# Use node if available, fall back to printf-based JSON escaping
+if command -v node &>/dev/null; then
+  node -e "
+    const content = require('fs').readFileSync('/dev/stdin', 'utf8');
+    console.log(JSON.stringify({
+      hookSpecificOutput: { additionalContext: content }
+    }));
+  " <<< "$CONTENT"
+else
+  # Portable fallback: escape for JSON using sed
+  ESCAPED=$(printf '%s' "$CONTENT" | sed -e 's/\\/\\\\/g' -e 's/"/\\"/g' -e ':a;N;$!ba;s/\n/\\n/g')
+  printf '{"hookSpecificOutput":{"additionalContext":"%s"}}' "$ESCAPED"
+fi