feat(summon): add react application, route, and wrapper generators

[advl]

Done

• Add @canonical/summon-application with three generators:
  • summon application react --ssr --router: scaffolds a full React SSR app with router integration, grouped routes via wrapper() + group(), withI18n middleware, and working SSR entry points
  • summon route <path>: generates a route module and appends its export
  • summon wrapper <name>: generates a wrapper module and appends its export
• Generator templates emit declare module augmentation, RouteMiddleware-typed middleware, proper RouterDehydratedState usage, single RouterProvider
• Replace relative cross-package imports with @canonical/summon-core, @canonical/task
• Fix peer dep ranges to ^0.22.0
• Register generators in packages/cli/summon/generators/

Depends on #601 and #602

QA

• bun run --filter @canonical/summon-application test — 7 tests pass
• Verify summon application react --ssr --router --app-path=test-app generates a valid project

PR readiness check

• PR should have one of the following labels:
  • Feature 🎁
• PR title follows the Conventional Commits format.
• The code follows the appropriate code standards
• All packages define the required scripts in package.json:
  • All packages: check, check:fix, and test.
• If this PR introduces a new package: first-time publish has been done manually from inside the package directory using npm publish --access public.