fix(biome): find root when using biome.jsonc (#4774)

Since biome supports either `biome.json` or `biome.jsonc` config files,
we need to look for both when searching for the LSP project root. We can
also look for a package.json or .git folder to use. This uses mostly the
same logic as deno.

autoload/ale/handlers/biome.vim

@@ -5,6 +5,7 @@ call ale#Set('biome_executable', 'biome')
 call ale#Set('biome_use_global', get(g:, 'ale_use_global_executables', 0))
 call ale#Set('biome_options', '')
 call ale#Set('biome_fixer_apply_unsafe', 0)
+call ale#Set('biome_lsp_project_root', '')
 
 function! ale#handlers#biome#GetExecutable(buffer) abort
     return ale#path#FindExecutable(a:buffer, 'biome', [
@@ -30,7 +31,35 @@ function! ale#handlers#biome#GetLanguage(buffer) abort
 endfunction
 
 function! ale#handlers#biome#GetProjectRoot(buffer) abort
-    let l:biome_file = ale#path#FindNearestFile(a:buffer, 'biome.json')
+    let l:project_root = ale#Var(a:buffer, 'biome_lsp_project_root')
 
-    return !empty(l:biome_file) ? fnamemodify(l:biome_file, ':h') : ''
+    if !empty(l:project_root)
+        return l:project_root
+    endif
+
+    let l:possible_project_roots = [
+    \   'biome.json',
+    \   'biome.jsonc',
+    \   'package.json',
+    \   '.git',
+    \   bufname(a:buffer),
+    \]
+
+    for l:possible_root in l:possible_project_roots
+        let l:project_root = ale#path#FindNearestFile(a:buffer, l:possible_root)
+
+        if empty(l:project_root)
+            let l:project_root = ale#path#FindNearestDirectory(a:buffer, l:possible_root)
+        endif
+
+        if !empty(l:project_root)
+            " dir:p expands to /full/path/to/dir/ whereas
+            " file:p expands to /full/path/to/file (no trailing slash)
+            " Appending '/' ensures that :h:h removes the path's last segment
+            " regardless of whether it is a directory or not.
+            return fnamemodify(l:project_root . '/', ':p:h:h')
+        endif
+    endfor
+
+    return ''
 endfunction