Swift: add the v1.0 basic-catalog examples to the sample gallery, and test every example #3624

The Swift sample gallery (swift/sample) bundles only the v0.9.1 basic-catalog examples (SampleLoader.swift loads one examples folder, and the Xcode project points only at specification/v0_9_1/catalogs/basic/examples). Blueprint §9 (blueprints/modules/a2ui_framework_adapter.blueprint.md) asks for a protocol version selector and at least one v1.0 sample, and the Lit, React and Angular galleries (and Flutter in #3620) load catalogs/basic/v1/examples behind a selector.

There is also no Swift test that processes the basic-catalog examples. Flutter has dart/a2ui_flutter/test/catalog/basic/examples_test.dart and Lit has basic-catalog-examples.test.ts; the only Swift test that reads an example covers a single file.

Proposal, as two small PRs:

1. Gallery: bundle catalogs/basic/v1/examples as a second folder, tag each sample with its protocol version, and add a segmented v0.9.1 / v1.0 picker. The processor already registers every basic catalog version.
2. Tests: a parameterized Swift Testing case over both example folders that feeds each example to MessageProcessor with the basic catalogs (and stand-ins for custom components) and asserts no errors and a resolved root. Any example that fails would be listed with a linked issue rather than skipped silently.

Would you take these? If so, could this be assigned to me?