feat: the public @ekklesia package release train, built, reproduced, and proven (ADR 0053)

Produces the exact public package tarballs of a platform release, validates
them, and proves a standalone module consumes those artifacts end to end.
Nothing is published and no credential is configured.

- scripts/package-release.ts (pnpm packages:release) is the canonical
  release builder: from a clean commit it rebuilds the nine public
  packages from clean output, packs each, inspects every tarball, checks
  the release set and coordinated versions, and only then writes
  ekklesia-packages-<version>/ with the tarballs, SHA256SUMS, and a
  provider-neutral manifest (ekklesia-package-train.json: version,
  revision, and each package's file, size, SHA-256, npm integrity).
- Packing uses a pack-only pnpm beforePacking hook (passed with
  --config.pnpmfile, never the workspace's install settings). pnpm inserts
  rewritten workspace: dependencies in async completion order, so two
  checkouts of one commit packed module-pack's package.json with keys in a
  different order; the hook restores the source key order (and the
  inspection enforces it). It also drops devDependencies, which named
  private packages outside the train.
- scripts/test-package-release.sh (pnpm test:package-release, the CI
  package-release gate) builds the train twice, the second time from a
  separate worktree, requires byte-identical release directories, then
  runs the standalone consumer proof on the release: manifest checked,
  offline install from the tarballs only, lockfile integrity equal to the
  manifest's, frozen-lockfile reinstall, no Drizzle, one React, contracts
  only transitive, every @ekklesia package and module-pack at the release
  version, skipLibCheck: false, UI build, pack, and Core verification.
- docs/development/releases.md documents the release order, the train,
  the artifacts, and the reproducibility findings; registry publication
  remains unimplemented.
- ADR 0053 is Accepted: everything it decides that does not need a
  registry is now proven, and registry provisioning is on its own
  Deferred list.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

docs/development/testing.md

@@ -649,6 +649,17 @@ Ekklesia Module Package v1 (ADR 0049) is proven at three levels, all in `pnpm ve
   builds the template and Core first, and runs the template's own tests (which rebuild its UI in
   place) before these.
 
+## The public package train
+
+`pnpm test:package-release` (the CI `package-release` job) builds the public `@ekklesia/*` package
+train, proves a second build from another checkout of the commit byte-identical, and installs
+exactly those tarballs into the standalone fixture module, offline, which must typecheck with
+`skipLibCheck: false`, build, package, and verify. It needs a clean source tree; pass
+`-- --allow-modified` to try uncommitted changes locally. The release rules themselves (set,
+versions, manifest inspection, release directory, manifest bytes, the pack hook) are unit-tested in
+`tests/public-packages.test.ts`, part of `pnpm verify`. See
+[Releases and the public package train](releases.md).
+
 ## The generic platform image and the reference deployment
 
 These need Docker and build images locally; nothing is pushed or published.