Revert "tools: fix file_edit and file_write to write directly, not via temp+rename"

This reverts commit ce1688efb8.

tools/file_edit

@@ -6,6 +6,7 @@ import sys
 import os
 import hashlib
 import difflib
+import tempfile
 
 def marker_path(file_path):
     h = hashlib.sha256(file_path.encode()).hexdigest()[:64]
@@ -113,10 +114,13 @@ if err:
     print(f"error: {err}")
     sys.exit(1)
 
+tmp = tempfile.NamedTemporaryFile(mode='w', dir=os.path.dirname(file_path) or '.', delete=False)
 try:
-    with open(file_path, 'w') as f:
-        f.write(new_content)
-except OSError as e:
+    tmp.write(new_content)
+    tmp.close()
+    os.replace(tmp.name, file_path)
+except Exception as e:
+    os.unlink(tmp.name)
     print(f"error: {e}")
     sys.exit(1)
 

tools/file_write

@@ -6,6 +6,7 @@ import sys
 import os
 import hashlib
 import difflib
+import tempfile
 
 def marker_path(file_path):
     h = hashlib.sha256(file_path.encode()).hexdigest()[:64]
@@ -39,10 +40,14 @@ if exists:
     with open(file_path, 'r', errors='replace') as f:
         old_content = f.read()
 
+os.makedirs(os.path.dirname(file_path) or '.', exist_ok=True)
+tmp = tempfile.NamedTemporaryFile(mode='w', dir=os.path.dirname(file_path) or '.', delete=False)
 try:
-    with open(file_path, 'w') as f:
-        f.write(content)
-except OSError as e:
+    tmp.write(content)
+    tmp.close()
+    os.replace(tmp.name, file_path)
+except Exception as e:
+    os.unlink(tmp.name)
     print(f"error: {e}")
     sys.exit(1)