fix(compiler): do not auto-open on one-shot compile

Problem: auto-open fired on :Preview compile, which is a one-shot
build. Users compiling to check for errors or rebuild with the viewer
already open got an unexpected browser/viewer window.

Solution: gate auto-open on not opts.oneshot so it only fires during
toggle/watch mode, where opening the viewer on first compile is the
intended behaviour.

lua/preview/compiler.lua

@@ -162,6 +162,7 @@ function M.compile(bufnr, name, provider, ctx, opts)
 
     if
       provider.open
+      and not opts.oneshot
       and not opened[bufnr]
       and output_file ~= ''
       and vim.uv.fs_stat(output_file)
@@ -240,6 +241,7 @@ function M.compile(bufnr, name, provider, ctx, opts)
         end
         if
           provider.open
+          and not opts.oneshot
           and not opened[bufnr]
           and output_file ~= ''
           and vim.uv.fs_stat(output_file)

lua/preview/presets.lua

@@ -246,7 +246,7 @@ M.asciidoctor = {
   ft = 'asciidoc',
   cmd = { 'asciidoctor' },
   args = function(ctx)
-    return { ctx.file, '-o', ctx.output }
+    return { '--failure-level', 'ERROR', ctx.file, '-o', ctx.output }
   end,
   output = function(ctx)
     return (ctx.file:gsub('%.adoc$', '.html'))

spec/presets_spec.lua

@@ -467,7 +467,7 @@ describe('presets', function()
 
     it('returns args with file and output', function()
       assert.are.same(
-        { '/tmp/document.adoc', '-o', '/tmp/document.html' },
+        { '--failure-level', 'ERROR', '/tmp/document.adoc', '-o', '/tmp/document.html' },
         presets.asciidoctor.args(adoc_ctx)
       )
     end)