feat(icons): provide an icon for Astro

chore(languages): updated to include astro

fix:(build): process

chore(assets): updated icon

I made the icon much better.
If you want xsf file from gimp, dm me on discord: `eveeifyeve`

chore(assets): uncapitalised astro icon

fix(assets): astro sizing

fix(assets): image color to be single

fix(assets): icon position

chore(assets): made astro logo darker

src/mappings/language.rs

@@ -7,6 +7,7 @@ pub fn get<'a>(
         "Cord.unknown" => ("text", filetype),
         "autohotkey" => ("ahk", "AutoHotkey"),
         "asm" => ("assembly", "Assembly"),
+        "astro" => ("astro", "Astro"),
         "sh" => ("shell", "Shell script"),
         "c" => ("c", "C "),
         "clojure" => ("clojure", "Clojure"),