fix: correct typos and improve code clarity (#14341)

- Fix 'clipbard' typos in clipboard.rs (function names, comments, strings)
- Fix 'seperate' typo in x11/server.rs comment
- Replace !is_ok() with idiomatic is_err() in updater.rs
- Fix double backtick typo in updater.rs comment

Co-authored-by: Ocean <ocean@Mac-mini-von-Ocean.local>

libs/scrap/src/x11/server.rs

@@ -98,7 +98,7 @@ unsafe fn check_x11_shm_available(c: *mut xcb_connection_t) -> Result<(), Error>
     let mut e: *mut xcb_generic_error_t = std::ptr::null_mut();
     let reply = xcb_shm_query_version_reply(c, cookie, &mut e as _);
     if reply.is_null() {
-        // TODO: Should seperate SHM disabled from SHM not supported?
+        // TODO: Should separate SHM disabled from SHM not supported?
         return Err(Error::UnsupportedExtension);
     } else {
         // https://github.com/FFmpeg/FFmpeg/blob/6229e4ac425b4566446edefb67d5c225eb397b58/libavdevice/xcbgrab.c#L229