fix: rewrite hook in pure node — no bash/awk/sed portability issues

hooks/session-start

@@ -1,41 +1,32 @@
-#!/usr/bin/env bash
-# SessionStart hook for ArcheFlow plugin.
-# Injects the using-archeflow skill as additional context.
+#!/usr/bin/env node
+// SessionStart hook for ArcheFlow plugin.
+// Injects the using-archeflow skill as additional context.
 
-PLUGIN_ROOT="$(cd "$(dirname "$0")/.." 2>/dev/null && pwd)" || {
-  echo '{}'
-  exit 0
+const fs = require("fs");
+const path = require("path");
+
+try {
+  const pluginRoot = path.resolve(__dirname, "..");
+  const skillFile = path.join(pluginRoot, "skills", "using-archeflow", "SKILL.md");
+
+  if (!fs.existsSync(skillFile)) {
+    console.log("{}");
+    process.exit(0);
   }
 
-SKILL_FILE="${PLUGIN_ROOT}/skills/using-archeflow/SKILL.md"
+  const raw = fs.readFileSync(skillFile, "utf8");
 
-if [ ! -f "$SKILL_FILE" ]; then
-  echo '{}'
-  exit 0
-fi
+  // Strip YAML frontmatter
+  const stripped = raw.replace(/^---\n[\s\S]*?\n---\n?/, "");
 
-# Strip YAML frontmatter (everything between first two --- lines)
-CONTENT=$(awk 'BEGIN{skip=0} /^---$/{skip++; next} skip>=2{print}' "$SKILL_FILE" 2>/dev/null) || {
-  echo '{}'
-  exit 0
+  if (!stripped.trim()) {
+    console.log("{}");
+    process.exit(0);
   }
 
-if [ -z "$CONTENT" ]; then
-  echo '{}'
-  exit 0
-fi
-
-# JSON-escape and output
-if command -v node &>/dev/null; then
-  node -e '
-    const content = require("fs").readFileSync(0, "utf8");
-    console.log(JSON.stringify({ hookSpecificOutput: { additionalContext: content } }));
-  ' <<< "$CONTENT"
-else
-  # Portable fallback
-  ESCAPED=$(printf '%s' "$CONTENT" | sed -e 's/\\/\\\\/g' -e 's/"/\\"/g' -e ':a;N;$!ba;s/\n/\\n/g' 2>/dev/null) || {
-    echo '{}'
-    exit 0
+  console.log(JSON.stringify({
+    hookSpecificOutput: { additionalContext: stripped }
+  }));
+} catch (e) {
+  console.log("{}");
 }
-  printf '{"hookSpecificOutput":{"additionalContext":"%s"}}' "$ESCAPED"
-fi