move commandAction out of CmdLine.Seek

This is groundwork for nested seek loops, eg seeking over all files and
then performing commandActions on a list of remotes, which can be done
concurrently.

This commit was sponsored by Boyd Stephen Smith Jr. on Patreon.

Command/Fix.hs

@@ -34,8 +34,9 @@ seek ps = unlessM crippledFileSystem $ do
 		( return FixAll
 		, return FixSymlinks
 		)
-	l <- workTreeItems ps
-	flip withFilesInGit l $ whenAnnexed $ start fixwhat
+	withFilesInGit
+		(commandAction . (whenAnnexed $ start fixwhat))
+		=<< workTreeItems ps
 
 data FixWhat = FixSymlinks | FixAll