0.7.2

Faster, leaner import scanning

No change to the CLI's arguments or output.

• About 27× faster on large packages. swift-syntax now parses each file only up to the end of its last import declaration (ImportRegion, a byte scan), checked against 23,206 real Swift files to give the same imports as a full parse. A 2,040-file scan went from 766 ms to 29 ms, with 10× fewer allocations.
• Less memory. On swift-syntax itself (539 files) CPU time went from 0.85 s to 0.07 s and peak memory from 129 MB to 46 MB.
• SyntaxVisitor instead of SyntaxRewriter; PackageInformation decodes the object form first.
• The scanner lives in a new PackageGeneratorCore target (a product only for the benchmarks; not a stable API).
• New: architecture rules (swift-llm-check 0.5.0), benchmarks, CI, and a landing page at https://mackoj.github.io/PackageGeneratorCLI/.

Artifact bundle checksum: ad58ee6e61c2af07c563e76115c62de6659fcf63dd389db3fe90271f90905013