message templates: Add/update properties

[pboisver]

Motivation

CEDAR templates have to be correct AND match main. The templates from the mpog_pilot branch are now on main so CEDAR should match those. Other templates need to have updates and then be regenerated and updated on main.

• Add "Default display" and "has_causal_pathway" to @context, and populate "Default display" (refer to main if available, or else determine and update) and has_causal_pathway (new)
• Update message text to include comparator reference or adjust text
• in a few of cases (approach goal, drop below goal, opportunity to improve, reached goal) we have added a new "is about" element ("approach goal", "goal comparator content", etc.).

Check each template against CEDAR and update the templates. (Add to a branch and compare to main; should mostly be additions).