feat: stabilize typegen output order

[AkaraChen]

What changed

• Sort command and event template contexts immediately before rendering generated files.
• Sort generated type declarations with a local dependency-first ordering in the generator layer.
• Apply the same output ordering to vanilla TypeScript and Zod generation.
• Add an end-to-end regression test for stable generated order.

Scope

This avoids changing analysis traversal, lazy type resolution, dependency graph behavior, or cache hashing. Sorting is limited to generated output preparation.

Validation

• cargo fmt --check
• cargo test