feat: stores cover their tree, undone attempts read, contradicted origins blocked (v0.25.0)

[cskwork]

v0.25.0 — no unit outside the loop, undone attempts read, contradicted origins blocked

Three gaps let a change skip the kit's checks. A unit in a monorepo with no
.sdlc/ of its own was read as "no loop here". The History probe said "read
reverts" without saying how, so an earlier attempt that was rolled back for a
side effect went unread. And the Intent match lens counted Covered, Missing
and Beyond only, so a build that handled an origin detail with the opposite
rule (origin: expired coupons greyed out; build: hidden) could pass as
Covered. No new gate or check; no script-read line
changed.

Changes

• AGENTS.md "Monorepos", SKILL.md "When this skill runs": a store covers
  its whole tree. A change in a unit without its own .sdlc/ runs the loop in
  the nearest store above it, gates run from that store's directory.
• skills/1-intent "History": run git log --no-merges -i -E --grep='revert|rollback|back out' -- <paths> on the shipping branch, plus
  the project's own words for an undo; read each hit's ticket for the side
  effect that forced it.
• templates/intent.md: Researcher findings opens with a History: line —
  the search run and its hits, or none found with the command.
• roles/verifier.md Lens 3, templates/evidence.md: a fourth class,
  Contradicts — an origin detail built with a different rule. Blocking
  unless the origin owner's decision is recorded; an agent-proposed rule is
  not an override. The evidence line gains Contradicts: <list or none>.
• templates/spec.md: new Origin overrides section (R → origin text →
  owner's decision: who, date, words; none by default).
• roles/adversary.md Traceability: the same contradiction is blocking at
  the spec gate, before anything is built.
• README.md, README.ko.md: the monorepo line says the same.

Nothing to migrate.

Selftest: gates/selftest.sh → SELFTEST PASS