* docs: mark M5 complete (feature surface done), set M6 as next
* docs: correct HANDOFF service count to eight
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Co-authored-by: James Maes <jmaes@dmdbrands.com>
* docs: mark M1-M4 complete, set M5 as next milestone
Phase 3 feature completeness (Calendar, Contacts, JMAP, live Filters)
is done and merged to dev; update ROADMAP.md, the rendered roadmap
page, and HANDOFF.md to reflect it and point at M5 next.
* docs: correct service count to eight (Calendar+Contacts added)
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Co-authored-by: James Maes <jmaes@dmdbrands.com>