Add /dsp print artifact-output skill

[docreo]

Adds signalproof-print 0.1.0 and the print operator command.

Core behavior:

• /dsp print or /dsp print <target> => DOCX + PDF + Google Doc.
• /dsp print <type> => requested type for current bounded item.
• @<name> resolves an exact named artifact/document.
• explicit Git/server paths are source selectors, not blanket write authority.
• Google Docs output MUST import/upload the completed formatted DOCX.
• text-extraction/reconstruction into a blank Google Doc is an explicit regression anti-pattern.
• failed Google conversion blocks only the Google output; successful DOCX/PDF siblings remain valid.

Acceptance: 12/12 PASS in acceptance/signalproof-print-v0.1-acceptance.md.

Private continuity logged separately in docreo/Signalproof-Build-Ledger.