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-cross-store.ct

@@ -1,8 +1,8 @@
 # Cross-store move
 $ pda set key@src value
 $ pda mv key@src key@dst
-  ok  renamed key@src to key@dst
+  ok renamed key@src to key@dst
 $ pda get key@dst
 value
 $ pda get key@src --> FAIL
-FAIL  cannot get 'key@src': no such key
+FAIL cannot get 'key@src': no such key