Reconcile Harn truth after contributor PRs #15, #9, and #7

[rjx18]

Summary

The original contributor PRs #15, #9, and #7 were intentionally merged first so GitHub preserves each contribution as MERGED. This maintainer follow-up honestly reconciles current Harn truth; it does not claim Harn plans predated contributor commits.

• reconcile pnpm build approvals from fix(deps): add allowBuilds for pnpm 10.26+/11 alongside onlyBuiltDependencies #15 with one anchored workspace declaration and an executable release-audit equivalence check against package.json
• anchor install and Tailscale disclosure truth from docs: document Tailscale HTTPS prerequisite, pnpm dlx limitation, and build-approval setting #9 without rewriting contributor prose
• reconcile narrow Grok translation, launch, catalog, control, environment, and lifecycle truth from feat: add Grok CLI adapter #7; add only the missing $0.30/M short-context cached-input price and focused regression

Harn plans

• reconcile-pr15-pnpm-build-approvals
• reconcile-pr9-install-tailscale-disclosure
• reconcile-pr7-grok-truth

Each plan was checked and locked on a clean worktree before implementation, then applied in its matching implementation commit.

Validation

• pnpm install --frozen-lockfile
• pnpm -r build
• Grok package build and tests: 3 files, 6 tests
• switchboard pricing and registry: 2 files, 32 tests
• exact Grok CLI attach-resolution regression: 1 test
• website verification and web-next production build through recursive build
• pnpm -r test reproduced only the accepted pre-existing ACP fixed-50ms cancellation startup race
• isolated ACP cancellation: 1/1 passed in 62ms
• isolated ACP package: 14/14 passed

No ACP source or tests were changed. Issue #6, issue #8, and draft PRs #10-#14 are outside this PR and remain untouched.