feat(git): improve options in gitconfig

Based on some options explored at
jvns.ca/blog/2024/02/16/popular-git-config-options

dots/.config/git/config

@@ -16,10 +16,12 @@
 	diffFilter = delta --color-only --features=interactive
 
 [merge]
-	conflictstyle = diff3
+	conflictstyle = zdiff3
 
 [diff]
 	colorMoved = default
+	submodule = log
+	tool = nvimdiff
 
 [delta]
 	navigate = true
@@ -65,6 +67,7 @@
 [log]
 	abbrevCommit = true
 	decorate = short
+	date = iso
 [apply]
 	ignoreWhitespace = change
 [rerere]
@@ -74,3 +77,19 @@
 	threeWay = true
 [gpg "ssh"]
 	allowedSignersFile = ~/.config/git/allowed_signers
+[rebase]
+	autosquash = true
+	autostash = true
+	updateRefs = true
+[transfer]
+	fsckobjects = true
+[fetch]
+	fsckobjects = true
+	prune = true
+	prunetags = true
+[receieve]
+	fsckObjects = true
+[status]
+	submoduleSummary = true
+[submodule]
+	recurse = true