S0232-cli-release-1: run the outside-the-repo install gate on the release path

[NSchatz]

Spec: work/specs/S0232-cli-release-1/spec.md (umbrella).

@cosyte/cli@0.0.1 and 0.0.2 are on npm permanently uninstallable, and the check that catches that
shape was a sentence in a human checklist: a --dry-run packs a tarball but never resolves its
dependencies from a registry. This makes it a step the release path executes.

What is here

• scripts/release-install-gate.mjs. Packs this tree with pnpm pack, installs the packed
  tarball with npm install into a fresh directory outside the repository working tree (and
  refuses one inside it), executes every declared bin from the installed copy, and refuses a
  local-path specifier (file:, link:, a relative or absolute path) in dependencies,
  optionalDependencies or peerDependencies before it packs anything. devDependencies is
  reported and exempt: no consumer install resolves it, and this manifest carries one on purpose.
• One rule covers both bin shapes: a process that exits non-zero inside the window did not run.
  cosyte exits 0; cosyte-mcp is a stdio server that never exits on its own and is still serving
  at the end of its window. A process that has exited is never reported as still running, however
  late its pipes close.
• It fails closed, with a distinct reason per class: install-failed, bin-missing (a packaging
  defect, worded so it does not read like an install failure), bin-failed,
  local-path-specifier, and gate-timeout / gate-registry-unreachable / gate-error for a run
  that reached no verdict at all.
• .github/workflows/release.yml gains an install-gate job, and the publishing job needs: it
  with no if: on either, so a red or skipped gate stops the publish. The caller's four permission
  grants are unchanged. ci.yml is untouched and no step moved out of its verify job.
• RELEASING.md now presents the install as something the pipeline does, says what the gate does
  not cover, and keeps the version-string check as the human step it still is.

Negative controls (test/release-install-gate.test.ts, 27 cases)

A deliberately broken consumer specifier reds the gate, in each of the three fields and each shape a
local path takes. This repository's own unmodified manifest passes, and the report shows the gate
saw the file: devDependency rather than passing because it never looked. An installed copy
carrying neither @cosyte/fhir nor @cosyte/transform passes. A bin whose target is not in the
tarball reds as a packaging defect with the install recorded as having exited zero. A bin that exits
non-zero on load reds, naming the bin and its first diagnostic line. A manifest declaring no bin at
all reds rather than passing vacuously. And the workflow reader carries its own negative control, so
a publish job with no needs: cannot pass over it.

Evidence

pnpm lint, pnpm format:check, pnpm typecheck, pnpm test (39 files, 717 tests, was 690),
pnpm test:coverage (core 97.84 / commands 98.53 statements, unchanged: no src/ code here),
pnpm check:no-emdash, pnpm check:no-internal-refs, pnpm check:agent-notes, pnpm phi-scan,
pnpm smoke and pnpm attw all green. The gate itself was run end to end against this tree:
@cosyte/cli packs, installs outside the tree, cosyte exits 0 and cosyte-mcp is still running.

No dependency was added, no manifest field moved, and nothing a consumer receives changed.