fix: make Codex hooks transactional

src/plugins/guard-template.ts

@@ -16,6 +16,7 @@ export function generateGuardScript(
 'use strict';
 
 // Elydora agent guard for ${agentName}. Generated by @elydora/sdk.
+const crypto = require('node:crypto');
 const fs = require('node:fs');
 const path = require('node:path');
 const os = require('node:os');
@@ -55,9 +56,13 @@ function blockAgent(status) {
 function readStatusCache() {
   let raw;
   try {
-    raw = fs.readFileSync(STATUS_CACHE_PATH, 'utf-8');
+    raw = readProtectedFile(
+      STATUS_CACHE_PATH,
+      'Status cache',
+      MAX_PROTECTED_CONFIG_BYTES,
+    ).toString('utf-8');
   } catch (error) {
-    if (error.code === 'ENOENT') return undefined;
+    if (hasRuntimeErrorCode(error, 'ENOENT')) return undefined;
     throw new Error('Failed to read status cache: ' + error.message);
   }
   let cache;
@@ -75,26 +80,10 @@ function readStatusCache() {
 }
 
 function writeStatusCache(status) {
-  const temporaryPath = STATUS_CACHE_PATH + '.' + process.pid + '.tmp';
-  try {
-    fs.writeFileSync(temporaryPath, JSON.stringify({
-      status,
-      cached_at: Date.now(),
-    }), { encoding: 'utf-8', mode: 0o600, flag: 'wx' });
-    try {
-      fs.renameSync(temporaryPath, STATUS_CACHE_PATH);
-    } catch (error) {
-      if (process.platform !== 'win32' || !['EEXIST', 'EPERM'].includes(error.code)) throw error;
-      try { fs.unlinkSync(STATUS_CACHE_PATH); } catch (unlinkError) {
-        if (unlinkError.code !== 'ENOENT') throw unlinkError;
-      }
-      fs.renameSync(temporaryPath, STATUS_CACHE_PATH);
-    }
-  } finally {
-    try { fs.unlinkSync(temporaryPath); } catch (error) {
-      if (error.code !== 'ENOENT') throw error;
-    }
-  }
+  writeProtectedJson(STATUS_CACHE_PATH, 'Status cache', {
+    status,
+    cached_at: Date.now(),
+  });
 }
 
 async function readInput() {
@@ -103,12 +92,14 @@ async function readInput() {
   const raw = Buffer.concat(chunks).toString('utf-8').trim();
   if (!raw) {
     if (FAIL_CLOSED) throw new Error('Hook input is empty');
+    process.stderr.write('[Elydora guard] Hook input is empty; enforcement continued in fail-open mode.\\n');
     return;
   }
   try {
     JSON.parse(raw);
   } catch (error) {
     if (FAIL_CLOSED) throw new Error('Hook input is invalid JSON: ' + error.message);
+    process.stderr.write('[Elydora guard] Hook input is invalid JSON; enforcement continued in fail-open mode: ' + error.message + '\\n');
   }
 }