feat: cmd-57 allow isolated news feed customizing

[wesleyboar]

Overview

Allow a client CMS to customize only the news feed list.

Rather than clone all of `post_list.html`, a cleint can clone and edit just the new `post_loop` block.

Status

• [x] add block (untested)
• [x] test on tup-ui
• [x] create tup-ui PR

Related

• CMD-57
• replaces #751
• required by https://github.com/TACC/tup-ui/pull/373

Changes

• added post_loop block to post_list.html template
• moved post_list.html template to /tacc so a client (that is not a Python app) can extend it

Testing

1. Have custom CMS with Blog/News installed.
2. Have sample blog posts.

3. Add taccsite_custom/tup_cms/templates/djangocms_blog/post_list.html with

   {% extends "djangocms_blog/post_list.html" %}
   
   {% block post_list %}
       {% for post in post_list %}
           <h2>{{ post.title }}</h2>
       {% endfor %}
   {% endblock %}

4. Load CMS Blog/News page.
5. Verify news page shows <h2> title for every post, but no other content/data.

UI

Skipped. But would be similar to https://github.com/TACC/Core-CMS/pull/751.

[wesleyboar]

Closed because CMD-57 can not be achieved this way without breaking pagination (limitation discovered in https://github.com/TACC/tup-ui/pull/373).

[wesleyboar]

Superseded by CMD-97.