Sync Boatstack from Intelligence Flow Labs @ 3e8ad57097ee

[operator-stack-publisher]

What this sync releases

Evidence capabilities are now a shared, extensible substrate

Boatstack's PR evidence detection is no longer hard-wired to a single evidence
type. A generic evidence-capability registry now backs the "can this repository
produce the evidence?" cut, and visual evidence is its first tenant. Nothing
changes in how visual evidence behaves today — the same repository commands,
statuses, and fingerprints — but the shared spine means future evidence types
(and the upcoming capture and provisioning flows) plug in through one registry
instead of a bespoke path each time.

Publishing toolkit moved to a standalone package

The labkit toolkit that projects Boatstack into this repository moved from a
submodule of the monorepo's Python package to a standalone top-level labkit/
project, invoked as python -m labkit. This only changes where the publishing
tooling lives and how the sync workflow installs it; the projected files are
byte-for-byte identical (asserted by the golden reproduction test), with no
effect on Boatstack's runtime, CLI, skill, or public contract.

Projection provenance

Generated from operatorstack/intelligence-flow@3e8ad57097eea39260ae67102997bdbd316faf17.
Review provenance, tests, examples, and context-cost changes before merging.

[bigboateng]

Closing: superseded stale sync. Intermediate snapshot from the old workflow; conflicts with main after the labkit control-plane migration (#83) and upstream has advanced past this commit. A fresh engine-driven sync for the current tip replaces it.