v12.0.0-beta.8

Merged

• Refactor build and watch internals into cohesive subsystems #333
• Add CLI subcommands and command-specific help #332
• Speed up tests and prune redundant coverage #331

Commits

• Separate example-site acceptance tests from subsystem regressions c2bec1f
• refactor(watch): isolate lifecycle, dependency routing, and output ownership f1a0197
• refactor(build-pages): separate orchestration, data, generation, and outputs 6bd279f