bug#49208: 28.0.50; project-find-regexp's xref-mode result buffer is not editable

[Christian Tietze <me@christiantietze.de>]

Sorry, I thought these were staples of the Emacs landscape with
`wdired' being the ancestor of them all. You know that one? If no,
check it out for in-place file renaming in dired listings, including
rectangle-mode (or multiple cursors, if one prefers) changes.

Not sure how to best implement this, and larger elisp code bases
are hard to follow for me still; it sounds like a problem I'd tackle
by storing the original, making an editable copy, then diffing the
buffers on commit ([C-c C-c]) and apply the diffs per reference. In
dired, apply line changes as renames; in wgrep, apply per-file diffs.
Xref has file references for each item already, so I can imagine
applying the changes might not be that difficult, since [r] offers
replacement among all findings in a similar way, but only
mass-replacements, not amendmends and free-form editing.

This is my first contribution to the mailing list -- should I
rephrase/add anything to my original email to clarify, or is there
anything else I can do to help with filing this?

I guess a better title would be:

"Make project-find-refexp's xref-mode result buffer editable" instead
of the complaint-like way I phrased it to make it sound like a 'bug'.

Happy to follow along and help where I can!

-- Christian