feat: vfs - add stat syscall

programs/include/Api/Syscall.hpp

@@ -209,6 +209,9 @@ namespace montauk::abi {
     // Absolute path of the running executable (for argv[0]).
     static constexpr uint64_t SYS_GETEXECPATH         = 151;  // (index, flags) -> new front index; index=-1 queries support (1/0); flags bit0 = wait vsync
 
+    // Path metadata (size, timestamps, mode). (const char* path, FileStat* out) -> 0, -1 on error/unsupported.
+    static constexpr uint64_t SYS_STAT                = 152;
+
     // Tunable parameters (for SYS_SDR_SETPARAM / SYS_SDR_GETPARAM).
     static constexpr int SDR_PARAM_FREQ        = 0;  // center frequency, Hz
     static constexpr int SDR_PARAM_SAMPLE_RATE = 1;  // sample rate, Hz
@@ -287,6 +290,17 @@ namespace montauk::abi {
         uint8_t Second;
     };
 
+    // Path metadata returned by SYS_STAT. Timestamps are UTC unix seconds;
+    // a filesystem that does not record a given time reports it as 0.
+    struct FileStat {
+        uint64_t size;     // file size in bytes
+        int64_t  mtime;    // last data modification time
+        int64_t  ctime;    // last inode (metadata) change time
+        int64_t  atime;    // last access time
+        uint32_t mode;     // ext2/POSIX mode bits (type + permissions)
+        uint32_t isDir;    // 1 if the entry is a directory, else 0
+    };
+
     struct FbInfo {
         uint64_t width;
         uint64_t height;