Set file editor mode based on filename (#276)

Replaces `CodeMirror.findModeByExtension` with `findModeByFileName` to
detect nginx config files properly. If `CodeMirror.findModeByFileName`
doesn't match anything it automatically tries to find a match via
`findModeByExtension`. If that fails to return info as well, we try to
determine a mode by calling `CodeMirror.findModeByMIME`.

This is the discussion + pr in the CodeMirror repo:
* codemirror/codemirror5#2940
* codemirror/codemirror5#3027

Fixes #187

resources/js/store/modules/FileEditor.js

@@ -101,12 +101,10 @@ export default {
             commit('setTheme', theme);
         },
         async setMode({ commit }, value) {
-            const filename = (/.+\.(?<ext>[^.]+)$/u).exec(value);
             let mode = '';
 
-            const info = filename
-                ? CodeMirror.findModeByExtension(filename.groups.ext)
-                : CodeMirror.findModeByMIME(value);
+            const info = CodeMirror.findModeByFileName(value)
+                ?? CodeMirror.findModeByMIME(value);
 
             if (info) {
                 ({ mode } = info);