Schema inference: resolve string annotations, Annotated and NewType (#27)

[thorwhalen]

Closes #27.

• resolve_annotations(func, parameters) (ju.util): evaluates string annotations via typing.get_type_hints (partials, callable instances, bound methods, classes), falling back to per-parameter eval; unresolvable ones are left as-is. Used by signature_to_json_schema.
• unwrap_optional also peels Annotated, NewType and type X = ... aliases (top level and union members), which feeds is_type and array items.
• Array items inference now hands a custom param_to_prop_type a Parameter carrying the owning parameter's real name (was _).
• Tests in ju/tests/annotations_test.py (under from __future__ import annotations).

Review: fresh Opus reviewer: fix-then-merge. Confirmed and fixed: a recursive type alias crashed with RecursionError (items nesting now bounded), a cycle of aliases looped forever (now detected), a class defining only __new__ kept string annotations (now resolved). Tests added for each.

🤖 Generated with Claude Code

Dependents gate: 11 pass, 1 fail (smart-cv, collection errors, pre-existing).