Use deterministic Go guide linting

[walker-tx]

Summary

• keep deterministic guide validation in the isolated Go module at tools/lint-guide, preserving grouped human/JSON output, target and finding order, and 0/1/2 contracts
• reconcile onto current main after the prerequisite factory series through PR fix(factory): bundle phase one guide context #178 merged: retain the live Kit factory, remove its duplicate public-module checker, and make the tested --meta-only mode a required partial-export compatibility surface
• provision production drafting and Factory CI from the same version authority: actions/setup-go@v5 with go-version-file: tools/lint-guide/go.mod, build once at ${{ runner.temp }}/lint-guide, and pass it to validation/tests through LINT_GUIDE_BIN
• build the same nested module in the factory image; preserve the local nested-module fallback and coordinator grouped-JSON/exit handling
• preserve URL-placement doctrine, migrated guides, generated public Go copies, and the Node 24 tooling pin; keep the deleted TypeScript client/pipeline only as clearly labeled historical plan context
• expose the exact current CLI usage as mise run lint-guide -- [--json] [--meta-only] <slug|guides/<slug>|path>…

Verification

• nested tools Go formatting, go test -count=1 ./... (2 packages), go vet ./..., and go mod tidy drift check
• CLI usage, target/error/JSON, and --meta-only contracts; all 21 published guides produce 0 findings
• factory regression suite: 11/11 test scripts pass with the prebuilt LINT_GUIDE_BIN
• actionlint on production/Factory CI workflows and shellcheck on changed factory scripts/tests
• public Go tests and bash go/check.sh, including generated-guide drift checks
• Factory CI, Mise, Docker, and workflow structural assertions all use tools/lint-guide; linux/amd64 production image build passes
• deleted pipeline and duplicate public-module linter are absent; stale active-reference searches and git diff --check pass; worktree is clean

Local Go commands used CGO_ENABLED=0 only for the known host macOS LC_UUID linker issue. The production Docker build used its target linux/amd64 platform on this arm64 host; no workaround changed product files.

Merge ordering

Historical ordering note: “Draft: prerequisite work mentioned by the author must merge before this PR.” The prerequisite factory series through PR #178 has merged, and this branch has been rebased and reconciled onto current main.