docs: fix build references stale since the container-build rework

[CybotTM]

PR #219 rebuilt the container build: the Dockerfile no longer compiles Go — its binary-selector stage copies pre-built binaries via COPY bin/raybeam-linux-* /tmp/, and .github/workflows/docker.yml was deleted. README and docs/development.md still described the old world.

README.md:8 — badge "Docker Build" pointed at actions/workflows/docker.yml, a file that no longer exists (dead badge). Now a "Release" badge pointing at release.yml. Re-pointed rather than removed because the container image build is a real job in release.yml, so a status badge for it still carries information; the existing "Latest Release" badge shows the version, not whether the last run was green. There is no dedicated container workflow to point at — .github/workflows/ holds ci.yml and release.yml, no container.yml.

docs/development.md:114 — the repo tree listed docker.yml # Docker image builds. Now ci.yml # Lint, test, coverage; the release.yml comment changed from "Binary releases" to "Binaries + container image".

docs/development.md:610-618 — the "GitHub Actions Workflows" section documented a Docker Build workflow (triggers: release publish, weekly cron, master push) that is gone, and a Release entry that was wrong on all three points (trigger is a v* tag push, not release publish; binaries cover linux 386/amd64/arm64/armv6/armv7, darwin amd64/arm64 and windows amd64, not "linux and darwin (amd64)"). Replaced by an accurate CI entry and a Release entry that also covers the container image and the SBOM/attestation assets. Facts read from release.yml and the netresearch/.github release-go-app.yml orchestrator it delegates to.

docs/development.md:626 — docker build -t raybeam:test . was documented as a local build. In a fresh checkout it fails: ERROR: failed to build: failed to solve: lstat /bin: no such file or directory (the COPY bin/raybeam-linux-* has nothing to copy). The block now cross-compiles first.

docs/development.md:632-633 (not in the original report) — docker build --target builder and --target runner were documented as "test multi-stage build". Both stages were removed by #219; each fails with target stage "builder"/"runner" could not be found (the runtime stage is unnamed now). Dropped, and replaced with a note on which binary name each platform maps to for a multi-platform build.

Every command in the new block was executed in a clean worktree, in the order documented, and all three succeed: CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -trimpath -o bin/raybeam-linux-amd64 ., then docker build -t raybeam:test ., then docker run --rm raybeam:test raybeam --version → raybeam version unknown (expected: the release pipeline injects the version via ldflags). The multi-platform mapping sentence is read off the Dockerfile's case statement and is not a runnable command, so it was not executed; a buildx multi-arch run was not attempted.

Not touched, but worth a follow-up: the Dockerfile's own header comment (lines 3-4) says the container job "downloads them back into bin/ via gh release download". It does not — release-go-app.yml's container job uses actions/download-artifact with pattern: binary-linux-*.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[github-actions]

Automated approval for maintainer PR

All automated quality gates passed. See SECURITY_CONTROLS.md for compensating controls.

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 74.70%. Comparing base (c78730a) to head (b758bbb).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #256   +/-   ##
=======================================
  Coverage   74.70%   74.70%           
=======================================
  Files          10       10           
  Lines         427      427           
=======================================
  Hits          319      319           
  Misses         88       88           
  Partials       20       20           

Flag	Coverage Δ
e2e	74.70% <ø> (ø)
integration	74.70% <ø> (ø)
unittests	74.70% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.