Engine: Inline comments on <% end %> on output blocks produce invalid Ruby (#1363)

## Version

herb 0.8.10 (commit `3a36f815b05b`)

## Summary

When `<% end # comment %>` closes a block opened inside a `<%= %>`
output tag, Herb appends the closing `))` *after* the comment text in
compiled Ruby. Since `#` starts a Ruby comment, the `))` become part of
the comment, leaving `__herb.h((` unclosed.

## Minimal reproduction

```erb
<%= render Foo.new do %>
  hello
<% end # comment %>
```

### Actual compiled Ruby (broken)

```ruby
_buf << __herb.h((render Foo.new do; _buf << '  hello
'.freeze; end # comment ))
```

The `))` after `# comment` is commented out — parens never close.

### Expected

The `))` should be placed *before* the comment, or the comment should be
stripped:

```ruby
_buf << __herb.h((render Foo.new do; _buf << '  hello
'.freeze; end )) # comment
```

### Prism parse errors

```
- unexpected end-of-input, assuming it is closing the parent top level context (line 4)
- expected a matching `)` (line 5)
- unexpected end-of-input; expected a `)` to close the arguments (line 4)
```

## Scope

- **Affected:** `<% end # ... %>` closing a block started in `<%= %>`
(where Herb wraps in `__herb.h((...))`)
- **Not affected:** `<% end # ... %>` inside non-output `<% %>` tags —
no wrapping parens, so comment is harmless

## Workaround

Remove inline comments from `end` tags that close output-tag blocks.

---------

Signed-off-by: Joel Hawksley <joelhawksley@github.com>

Author: joelhawksley

lib/herb/engine.rb

@@ -287,13 +287,9 @@ def add_expression_block_end(code, escaped: false)
       @src.chomp! if @src.end_with?("\n") && code_stripped.start_with?(" ")
 
       @src << " " << code_stripped
+      @src << "\n" if self.class.comment?(code_stripped)
       @src << (escaped ? "))" : ")")
-
-      @src << if code.include?("#") || trailing_newline
-                "\n"
-              else
-                ";"
-              end
+      @src << (trailing_newline ? "\n" : ";")
 
       @buffer_on_stack = false
     end

test/engine/engine_block_test.rb

@@ -107,5 +107,11 @@ class EngineBlockTest < Minitest::Spec
 
       assert_compiled_snapshot(template)
     end
+
+    test "inline comment on end inside output block does not break parens" do
+      template = "<%= render Foo.new do %>hello<% end # comment %>"
+
+      assert_compiled_snapshot(template)
+    end
   end
 end