aSPARK v0.4.0 - Graph-gates: an optional accelerant for the loop

Ceremonies that run /sprint-plan, /peer-review or /demo-day now notice an
installed, built aspark-graph on their own and use it to scope their work
faster - no install step, no flag, no config file. Absent, nothing
changes. Present but stale, unbuilt, or silent on a query, the ceremony
says so once and falls back to reading the project by hand, exactly as
before.

Plans can now name, per task, which files it touches (a 'files:' note in
the Definition of Done) - added only when knowable up front.

Six acceptance criteria ship as documented partials rather than full
passes, each with a named, structural reason; none is a broken feature,
and every one degrades safely to prior behavior.