bigclock: add 12-hour & seconds support (#805)

Added P,A,M characters to bigclock and added 12hr and seconds support to bigclock via `bigclock_12hr` and `bigclock_seconds` in the config.
![image](/attachments/e95accff-4822-4801-8159-94411a6c644f)
Image has bigclock_12hr and bigclock_seconds enabled.

Farsi characters for P,A,M are blank since I don't know what it would look like in their language. (should i have just used the english characters as a placeholder?)

Reviewed-on: https://codeberg.org/fairyglade/ly/pulls/805
Reviewed-by: AnErrupTion <anerruption@disroot.org>
Co-authored-by: RadsammyT <radsammyt@gmail.com>
Co-committed-by: RadsammyT <radsammyt@gmail.com>

src/bigclock.zig

@@ -51,6 +51,9 @@ fn toBigNumber(char: u8, bigclock: Bigclock) [SIZE]u21 {
         '7' => locale_chars.SEVEN,
         '8' => locale_chars.EIGHT,
         '9' => locale_chars.NINE,
+        'p', 'P' => locale_chars.P,
+        'a', 'A' => locale_chars.A,
+        'm', 'M' => locale_chars.M,
         ':' => locale_chars.S,
         else => locale_chars.E,
     };