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/config-init.ct

@@ -3,8 +3,8 @@ $ pda config init
 
 # Second init fails
 $ pda config init --> FAIL
-FAIL  config file already exists
-hint  use 'pda config edit' or 'pda config init --new'
+FAIL config file already exists
+hint use 'pda config edit' or 'pda config init --new'
 
 # Init --new overwrites
 $ pda config init --new