fix(windows): guard fcntl usage behind platform checks

- core.py: lazy import now branches to msvcrt on win32
- smart_install.py: _BubbleLock uses msvcrt.locking on win32, fcntl on POSIX
- Fixes 'Missing standard library module fcntl' crash on Windows CI

Author: 1minds3t

src/omnipkg/core.py

@@ -4196,7 +4196,10 @@ def _heal_corrupt_metadata(self, install_path: Path, expected_package_name: str)
         """
         NUCLEAR HEALING with file locking to prevent race conditions
         """
-        import fcntl
+        if sys.platform == "win32":
+            import msvcrt
+        else:
+            import fcntl
 
         healed_count = 0
 
@@ -4212,8 +4215,8 @@ def _heal_corrupt_metadata(self, install_path: Path, expected_package_name: str)
             try:
                 with open(lock_file, "w") as lock_fd:
                     # Acquire exclusive lock
-                    fcntl.flock(lock_fd.fileno(), fcntl.LOCK_EX)
-
+                    if _sys.platform != "win32":
+                        fcntl.flock(lock_fd.fileno(), fcntl.LOCK_EX)
                     try:
                         content = metadata_file.read_text(encoding="utf-8", errors="ignore")
 
@@ -4240,10 +4243,11 @@ def _heal_corrupt_metadata(self, install_path: Path, expected_package_name: str)
                                 _("   🔧 AUTO-HEALED: Injected 'Name: {}' into {}/METADATA").format(pkg_name, dist_info.name)
                             )
                             healed_count += 1
-
+                        
                     finally:
                         # Release lock
-                        fcntl.flock(lock_fd.fileno(), fcntl.LOCK_UN)
+                        if _sys.platform != "win32":
+                            fcntl.flock(lock_fd.fileno(), fcntl.LOCK_UN)
 
             except Exception as e:
                 safe_print(_('   ⚠️  Failed to heal {}: {}').format(dist_info.name, e))

src/omnipkg/installation/smart_install.py

@@ -14,7 +14,9 @@
 from __future__ import annotations
 
 import contextlib
-import fcntl
+import sys
+if sys.platform != "win32":
+    import fcntl
 import json
 import os
 import shutil
@@ -82,18 +84,22 @@ def __init__(self, pkg_name: str, version: str, blocking: bool = True):
 
     def __enter__(self):
         self._fd = open(self.path, "w")
-        flag = fcntl.LOCK_EX if self.blocking else (fcntl.LOCK_EX | fcntl.LOCK_NB)
         try:
-            fcntl.flock(self._fd, flag)
-        except BlockingIOError:
+            if _sys.platform == "win32":
+                import msvcrt
+                msvcrt.locking(self._fd.fileno(), msvcrt.LK_NBLCK if not self.blocking else msvcrt.LK_LOCK, 1)
+            else:
+                flag = fcntl.LOCK_EX if self.blocking else (fcntl.LOCK_EX | fcntl.LOCK_NB)
+                fcntl.flock(self._fd, flag)
+        except (BlockingIOError, OSError):
             self._fd.close()
             self._fd = None
             raise BubbleLockBusy(f"Another process is already creating bubble for {self.path}")
         return self
-
     def __exit__(self, *_):
         if self._fd:
-            fcntl.flock(self._fd, fcntl.LOCK_UN)
+            if _sys.platform != "win32":
+                fcntl.flock(self._fd, fcntl.LOCK_UN)
             self._fd.close()