cargo doc complains about some urls that are not turned into links

so turn them into links.

rust/src/file.rs

@@ -65,7 +65,7 @@ fn get_error<T>() -> Result<T, Error> {
 /// [`libc::FILE`](https://docs.rs/libc/0.2.80/libc/enum.FILE.html)
 ///
 /// The notcurses `FILE` type [`FILE_NC`] a struct imported through bindgen,
-/// while the equivalent [`libc`][https://docs.rs/libc] crate FILE
+/// while the equivalent [`libc`](https://docs.rs/libc) crate FILE
 /// ([`FILE_LIBC`]) is an opaque enum.
 ///
 /// Several methods are provided to cast back and forth between both types,

rust/src/input/mod.rs

@@ -122,8 +122,8 @@ impl NcInput {
 /// Is this [char] a Supplementary Private Use Area-B codepoint?
 ///
 /// Links:
-/// - https://en.wikipedia.org/wiki/Private_Use_Areas
-/// - https://codepoints.net/supplementary_private_use_area-b
+/// - <https://en.wikipedia.org/wiki/Private_Use_Areas>
+/// - <https://codepoints.net/supplementary_private_use_area-b>
 #[inline]
 pub const fn nckey_supppuab_p(w: char) -> bool {
     w as u32 >= 0x100000_u32 && w as u32 <= 0x10fffd_u32