Diff summary generated regardless of full diff size

Description

When diffs in MRs or commits are large, both the summary (files added/changed/moved/deleted) and actual diff contents are clipped. The summary is valuable in its own right and should be shown in full, even if the full diff contents cannot.

Proposal

Since calculating a full diff summary can be done relatively cheaply using --raw on the diff command, I propose that the raw summary be generated/sent/rendered first & separately from the full diff contents. Once the actual diff contents are generated, the summary list items can be updated to link to their respective file's diff contents, if available.

Links / references

N/A

~"feature proposal"