[rdlabo]

Installation instructions currently request an unpublished npm 0.1.2 and describe the released Android SDK as unpublished. Pin the available npm beta with --save-exact, document its matching Swift revision and Maven Central 0.1.2 coordinate, and explain why the pre-rename v0.1.2 tag is not the matching Swift dependency.

Allow the existing package consumer suite to test a registry tarball with CONSUMER_PACKAGE. Allow native embedding fixtures to use an installed npm package with WORKERS_NPM_PACKAGE_DIR and a GitHub Swift revision with WORKERS_SWIFT_REVISION. Default local-checkout verification remains available. Document these controls and include package identity in future consumer reports.

Validation:

• 617 unit tests; TypeScript check; formatting; diff whitespace checks passed.
• Published npm beta: Vite/esbuild/browser ESM 10/10, Node/CommonJS 4/4, Vite dev 2/2, direct 26/26, isolated 22/22, 966 shared feature checks passed.
• Maven Central 0.1.2 with published npm beta: navigation, POST, rotation, close/reopen, startup failure, renderer loss, Activity recreation, broken entry and host cookie/service-worker isolation passed.
• Remote Swift revision plus published npm beta: normal, startup-failure and broken-entry scenarios passed on an iOS 27.0 simulator. The first normal attempt timed out during close; an unchanged rerun passed under the same deadline. Cause not established. No physical-device verification.
• Six iOS runner deadline tests passed.

This PR changes documentation and verification tooling only. Existing immutable versions and tags remain unchanged. npm stable 0.1.2 is still unpublished; the documented beta is installable today.