refactor(msg): single space between keyword and message, improve config suggestions

Tightens keyword formatting (ok/FAIL/hint/etc.) from two spaces to one.
Makes config key suggestions more generous: normalises spaces to
underscores, matches against leaf segments, and uses substring matching.
Updates all golden files.

testdata/mv-safe.ct

@@ -1,7 +1,7 @@
 $ pda set src@msf hello
 $ pda set dst@msf existing
 $ pda mv src@msf dst@msf --safe
-info  skipped 'dst@msf': already exists
+info skipped 'dst@msf': already exists
 $ pda get src@msf
 hello
 $ pda get dst@msf