fix: make help and version successful discovery

PRD.md

@@ -813,6 +813,12 @@ JSON mode is a strict framing protocol:
 - An error includes the path, byte size, and content digest of its Diagnostic
   Log when one is available.
 
+CLI discovery is the sole framing exception. `ghidr --help`, every
+`ghidr <command> --help`, and `ghidr --version` are successful metadata
+requests rather than operations: they emit plain UTF-8 text on stdout, leave
+stderr empty, exit with status 0, and never initialize Ghidra, access the
+Analysis Store, or execute a command.
+
 Human-readable mode may present progress and concise diagnostics on stderr.
 
 Every Ghidra/adapter invocation captures diagnostics into a private temporary