fix: !path treats '#' as end of arguments

[sg]

What changed

• !path argument parsing stops at the first #: it and all following text are ignored (message text is truncated at # before tokenizing).
• k and an explicit hop-path argument appearing before the # still work as before.
• Handle-level tests added; suite 112 passing. Docs updated.

Why

Text like !path #general fed #general into the path parser, producing a 'hops must be uniform hex' error instead of reporting the sender's route.

Breaking changes

None.

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