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/Dead.hs

@@ -29,7 +29,7 @@ optParser desc = (DeadRemotes <$> cmdParams desc)
 
 seek :: DeadOptions -> CommandSeek
 seek (DeadRemotes rs) = trustCommand "dead" DeadTrusted rs
-seek (DeadKeys ks) = seekActions $ pure $ map startKey ks
+seek (DeadKeys ks) = commandActions $ map startKey ks
 
 startKey :: Key -> CommandStart
 startKey key = do