chore: take vote-service out of the repository root

Removes the Go source, Dockerfile, go.mod, and Kubernetes manifests. The
deployed service is untouched and the review desk still calls it over
window.SKILLS_REVIEW_VOTE_API; only the source leaves.

The runbook does not leave. vote-service/README.md moves to
docs/vote-service.md, because it carries the parts that are hard to
rediscover: why the ingress overwrites X-Forwarded-For and Caddy stamps
X-Client-IP instead, why the image is side-loaded into containerd rather
than pulled, and why the PVC pins the Deployment to one node.

This drops verify.mjs from 84 assertions to 83. The removed one read
vote-service/main.go for X-Forwarded-For and 'one active vote per skill'
-- the review desk's only anti-abuse control -- and there is no file left
to read. It is the first assertion this repository has ever lost.

Rather than lower the gate's floor and leave a bare number behind,
gate.sh now subtracts the number of entries in
.agents/context/assertion-removals.md from the baseline. A removal costs
a written reason in a tracked file, in the same commit, as a visible
diff. Tested at 82 assertions: still refused.

Also drops the 22 MB of PNG baselines under .agents/snapshots/before/ and
before-reduced-motion/. They pictured the hand-written site, which no
longer exists; visual-regression.mjs has no compare mode to diff them
against; and they are recoverable from d88d8b8.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

README.md

@@ -59,8 +59,6 @@ bash .agents/scripts/gate.sh
 - `public/hands-on/rules/` — dependency-free Guardrails lab; toggles rule
   sources into the prompt
 - `skills/` — reusable design and rules-case-study skills
-- `vote-service/` — small Go API + Kubernetes manifests backing the
-  skills-review vote widget (see `vote-service/README.md`)
 - `GATES.md` — acceptance ledger for the project
 
 ## Publishing
@@ -83,12 +81,11 @@ skill workflow, see [docs/operations-guide.md](docs/operations-guide.md).
 ## Reader voting on the skills-review desk
 
 `skills-review/` is static, so its "which draft would you ship?" vote widget
-calls a separate stateful service — `vote-service/`, a small Go API on its own
-pod, one vote per visitor enforced server-side by IP (a MAC address is never
-visible to a server across the internet, so it cannot be used). See
-[vote-service/README.md](vote-service/README.md) for the API, the anti-abuse
-design, and the build/push/deploy steps; `src/pages/skills-review.astro` sets
-`window.SKILLS_REVIEW_VOTE_API` to point at it once deployed.
+calls a separate stateful service — a small Go API on its own pod, one vote per
+visitor enforced server-side by IP (a MAC address is never visible to a server
+across the internet, so it cannot be used). Its source no longer lives in this
+repository; the deployed service is unchanged. `src/pages/skills-review.astro`
+sets `window.SKILLS_REVIEW_VOTE_API` to point at it.
 
 ## Research