fix(contract-loader): strip inline comments from frontmatter values

[eeshsaxena]

Problem

The flat frontmatter parser in contract-loader.ts skips full-line # comments but does not treat an inline YAML comment as a comment, so it becomes part of the value.

The most visible impact is on kind. Given:

---
name: ingress # the edge node
kind: gateway # exposes a webhook
---

kind is read as the literal string "gateway # exposes a webhook". normalizeKind doesn't recognize that, so it silently falls back to the default "responsibility" — a gateway contract is mis-classified. id/name similarly keep their trailing comment text.

sliceContract("---\nkind: gateway # exposes a webhook\n---\n### Maintains\nx\n", "/x/g.prose.md").kind
// before: "responsibility"   (wrong)
// after:  "gateway"

Fix

Treat a whitespace-preceded # as an inline comment on unquoted scalars, so the value ends before it — matching YAML (a comment indicator must be preceded by whitespace) and the parser's existing full-line-comment handling.

• kind: gateway # note → gateway
• id: issue#42 → issue#42 (no whitespace before #, so literal)
• name: "release #1" → release #1 (quoted scalar, # literal)

Testing

Added two tests to contract-loader.test.ts (the inline-comment case and the literal-# cases). I also ran the real sliceContract end-to-end via tsx and all assertions pass. I couldn't run the full pnpm typecheck && test:runtime locally (dependency install was too slow in my environment), but the change is a small, localized edit to parseFlatFrontmatter and the type-only imports it touches are unchanged.

[eeshsaxena]

The reason this bites in practice: kind drives behavior (gateway/function/pattern/test vs the responsibility default), so a one-line inline comment on the kind field silently changes how a contract is treated, with no error. The fix follows YAML comment rules (a # only starts a comment when preceded by whitespace) so values like issue#42 and quoted scalars are untouched.