fix(narrow): File.write 长度实参加显式 ULONG(...)（避免 64→32 隐式窄化）

fileio.File.write(buf, count: ULONG) 的 count 是 32 位，而实参是 sizet/int64（strlen、pos、ir_len、total 等）；规则收紧后为隐式窄化，改为显式 ULONG(...)。本文件其它位置无隐式窄化。

App/lib/Phase/BuildPipeline.vp

@@ -131,7 +131,7 @@ def WriteCallSidecar(temp_dir: str, sha1: str, text: str) -> int:
         VLogger.error(f"--traceback: failed to write .vpcall (cannot open {vpath}), aborting compilation", "TRACEBACK")
         stdlib.free(vpath)
         return 1
-    vf.write(text, string.strlen(text))
+    vf.write(text, ULONG(string.strlen(text)))
     vf.close()
     return _tb_register_vpcall(vpath)
 
@@ -199,7 +199,7 @@ def TranslateFileGetTrans(mb: memhub.MemBuddy*, file_path: str, sha1_val: str, c
                 if pyi_path is not None:
                     pf: fileio.File* = fileio.File(pyi_path, fileio.MODE.W)
                     if not pf.closed:
-                        pf.write(pyi_buf, pyi_pos)
+                        pf.write(pyi_buf, ULONG(pyi_pos))
                         pf.close()
                     stdlib.free(pyi_path)
             stdlib.free(pyi_buf)
@@ -349,7 +349,7 @@ def write_ir_to_file(ir_buf: bytes, ir_len: sizet, output_dir: str, module_name:
     f: fileio.File* = fileio.File(path, fileio.MODE.W)
     if f.closed: return 1
 
-    written: int64 = f.write(ir_buf, ir_len)
+    written: int64 = f.write(ir_buf, ULONG(ir_len))
     f.close()
     if written < 0: return 1
     return 0
@@ -553,9 +553,9 @@ def _phase2_write_cmd(cmd: str) -> None:
         _phase2_bat_init = 1
         hdr1: str = "@echo off\r\n"
         hdr2: str = "rem TransPyV --phase2command generated commands\r\n"
-        f.write(hdr1, string.strlen(hdr1))
-        f.write(hdr2, string.strlen(hdr2))
-    f.write(cmd, string.strlen(cmd))
+        f.write(hdr1, ULONG(string.strlen(hdr1)))
+        f.write(hdr2, ULONG(string.strlen(hdr2)))
+    f.write(cmd, ULONG(string.strlen(cmd)))
     f.write("\r\n", 2)
     f.close()
 
@@ -2358,7 +2358,7 @@ def WriteStackMap(mb: memhub.MemBuddy*, exe_path: str) -> int:
     if mf.closed:
         VLogger.error(f"--traceback: failed to write sidecar file (cannot open {map_path}), aborting compilation", "TRACEBACK")
         return 1
-    mf.write(out, total)
+    mf.write(out, ULONG(total))
     mf.close()
     VLogger.success(f"--traceback: wrote address-to-source-line sidecar {map_path} ({uniq} records, {total} bytes)", "TRACEBACK")
     return 0