docs(docker-development): trim generic CI scaffolding, bump stale pins

[CybotTM]

Part of netresearch/skill-repo-skill#157. Ticks the docker-development-skill checkbox.

Rubric: netresearch/skill-repo-skill skills/skill-repo/references/skill-quality.md § "Body rules" / "When to split to references/" — content a one-line prompt regenerates (generic tutorials, restated public best practice, boilerplate) is a cut target; retro-born failure patterns, version/ecosystem facts, and inference-suppression rules are hard-protected.

Re-verification against current tree

Both audit-named targets still existed at origin/main (950264d) before this change:

• skills/docker-development/SKILL.md Quick Reference pinned node:20-alpine and golang:1.22-alpine.
• skills/docker-development/references/ci-testing.md (446 lines / 1897 words) carried multiple Problem/Solution tutorial sections restating public Docker/GH-Actions knowledge already summarized as one-liners in SKILL.md's own "CI Testing Gotchas" list.

What was cut (ci-testing.md, rubric test: one-line-prompt-regenerable)

• Pattern 1 Entrypoint Bypass, Pattern 2 DNS Mocking, Pattern 3 Compose Validation, Pattern 5 Secret Scanning — each is a generic tutorial already condensed to one line in SKILL.md § CI Testing Gotchas (items 1-4); the reference-file elaboration added no gotcha beyond restating the technique.
• Pattern 4's "Test Health Check Command" subsection — generic build/start/wait-loop/cleanup GH Actions boilerplate, no specific failure narrative.
• Pattern 6 Multi-Platform Build Testing, Pattern 7 Integration Testing with Service Containers — standard docker/setup-qemu-action / services: copy-paste boilerplate, no incident behind it.
• "Complete CI Workflow Example" (~55 lines) — restated patterns 1-3 verbatim as a full pipeline; nothing unique.

Net: 446 → 159 lines, 1897 → 1112 words (-785 words, -41%).

What was kept (retro-born, hard-protected)

• Worker/Sidecar HEALTHCHECK inheritance incl. the pgrep [m]essenger:consume self-match trap (renumbered Pattern 1; commit bbe9274).
• GitLab CI "image entrypoint must be a shell" sh -c gotcha (Pattern 2; commit 4b7e314).
• Restricted runner egress / build-time asset bundling (Pattern 3; commit 4b7e314).
• Built-image vs editable-install testing, __file__-relative data-path failure (Pattern 4; commit 4b7e314).
• Bake target docker-metadata-action inheritance (Pattern 5; commit 6979edf).
• "Local boot-test pitfalls" (port collision, foreground-log-to-file, distroless-no-shell, real-vs-benign log signals; commit b3aa6f7) — untouched.
• Patterns were renumbered 1-5 for a contiguous sequence (no external anchors/links referenced the old numbering — verified by repo-wide grep).

docker-via-wsl skill content untouched — no changes needed there.

Stale pins (SKILL.md Quick Reference)

Verified via mcp__package-version__check_docker_tags:

• node:20-alpine → node:24-alpine — Node 24 ("Krypton") is the current Active LTS (Docker Hub lts/lts-krypton tags resolve to 24.18.0); Node 26 is current only, not yet LTS.
• golang:1.22-alpine → golang:1.26-alpine — 1.26.5 is latest stable; 1.27 is still RC (1.27rc2/1.27-rc tags only).

This is a version bump, not a content cut — the illustrative Dockerfile examples stay.

Kept, borderline

None — every remaining section in ci-testing.md traces to a specific commit documenting a real incident/gotcha (verified via git log --oneline -- skills/docker-development/references/ci-testing.md), so no borderline calls were needed.

Verification

$ wc -w skills/docker-development/SKILL.md
500 skills/docker-development/SKILL.md   # exactly at the repo's 500-word hard cap, unchanged

$ bash skill-repo-skill/skills/skill-repo/scripts/validate-skill.sh .
OK: SKILL.md is 500 words (under 500 limit)
Errors: 0
Warnings: 6   # pre-existing README-template warnings, unrelated to this change

$ skill-repo-skill/scripts/audit-skills.sh .
SKILL: docker-development — BODY: 430 words, 119 lines [PASS] — REFERENCES: 4 total -> 4/P1 reachable, 0 ORPHAN
SKILL: docker-via-wsl      — BODY: 370 words, 55 lines [PASS]  — REFERENCES: 1 total -> 1/P1 reachable, 0 ORPHAN
SUMMARY: 2 skills, 0 FAIL, 2 WARN, 0 INFO, 0 ORPHAN refs

$ pre-commit run --files skills/docker-development/SKILL.md skills/docker-development/references/ci-testing.md
trim trailing whitespace .... Passed
fix end of files ............ Passed
Validate skill repo structure Passed
Plugin/SKILL/composer version parity Passed
markdownlint-cli2 ............ Passed
(yaml/actionlint/ruff/shellcheck: no matching files, skipped)

$ grep -rn "node:20\|golang:1\.22" .   # repo-wide
none

$ grep -rn "ci-testing.md" . --include="*.md"   # reference table + AGENTS.md + README.md + docs/ARCHITECTURE.md
all still resolve — file trimmed in place, not deleted, no dangling refs

DO NOT MERGE.

[github-actions]

Dependency Review

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

Scanned Files

None

[gemini-code-assist]

Code Review

This pull request updates the Node.js and Go base image versions in the multi-stage build examples in SKILL.md, and refactors ci-testing.md by removing several testing patterns and referencing them in SKILL.md instead. The review feedback correctly identifies that the proposed image tags (node:24-alpine and golang:1.26-alpine) refer to unreleased, non-existent versions, and recommends pinning to the current stable releases (node:22-alpine and golang:1.24-alpine) to avoid build failures.

Important

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[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