feat: discover registered RedwoodSDK routes and handlers

[bompus]

Behavior

Discover registered RedwoodSDK defineApp trees with literal/local-constant arrays, route, index, render, layout and prefix. Standard method tables keep HTTP methods, and handler arrays link only their final handler.

Ordinary handlers remain ANY /path unless their own returned JSX proves a page. Exact imported handler links and classification update after edits and deletion. Middleware, overridden worker exports and ambiguous method tables do not create invented page roots. Cross-file route arrays, custom methods and dynamic builders remain unsupported.

Validation

• Pinned RedwoodSDK 1.7.3 worker fixture and negative controls.
• Build and 91 focused WASM/control tests pass, including fresh compiled workers.
• Full native suite: 4,459 passed, 46 skipped.
• Independent correctness and complexity review is clear.

Stacked on codex/astro-route-links (PR #6).