Parser: Fix ERB control flow tags in attribute positions

[marcoroth]

This pull request fixes the parser to correctly handle ERB control flow tags when parsing HTML attributes.

Previously, control flow tags like <% if %>, <% end %>, and <%# comment %> were incorrectly included as part of attribute names and values. Now, only ERB output tags (<%=, <%==) can be part of attribute names, while control flow tags properly terminate attribute name and attribute value parsing.

This enables patterns like this, where there is no space between the closing %> and the attribute name:

<dialog data-controller="dialog" <% if condition %>data-turbo-permanent<% end %>></dialog>
<div <% if admin? %>data-admin data-role="admin"<% end %>></div>

Resolves #872
Resolves #1063

[pkg-pr-new]

npx https://pkg.pr.new/@herb-tools/formatter@873

npx https://pkg.pr.new/@herb-tools/language-server@873

npx https://pkg.pr.new/@herb-tools/linter@873

commit: f69460b

[github-actions]

🌿 Interactive Playground and Documentation Preview

A preview deployment has been built for this pull request. Try out the changes live in the interactive playground:

• Playground Preview
• Documentation Preview
• Website Preview

---

_{🌱 Grown from commit f69460b}

---

✅ Preview deployment has been cleaned up.