feat(opportunities): award fields and the awarded / awardee_uei filters

[makegov-mark]

What

Supports the opportunity and notice award fields added in Tango API 5.5.0.

• list_opportunities() gains two filters: awarded (bool) and awardee_uei (case-insensitive; OR several with |). Both search every opportunity rather than only active ones, so combine with active=True to narrow to open opportunities.
• The opportunity shape schema accepts awarded, award_date, award_amount, awardee, awardee_uei, award_count, solicitation_opportunity_id and an awards(...) expand (opportunity_id, notice_id, award_number, award_date, award_amount, awardee, awardee_uei). The same fields are accepted under list_vehicles(shape="opportunity(...)").
• The notice shape schema accepts award_date, award_amount, awardee and awardee_uei.
• Opportunity and Notice schema dataclasses gain the matching fields, and docs/API_REFERENCE.md gets a short section with an example.
• The vendored API contract is refreshed to 5.5.0, and tango/shapes/generated_overlay.py is regenerated from it. Types for the new paths are recorded in contracts/observed_shape_types.json so the generator resolves awarded as bool, award_amount as str, and awards as a list.

Caveats worth knowing

• The award leaves are filled only where SAM.gov posted an award notice; elsewhere they are null. award_amount is the text SAM.gov published, not a number.
• An award posted as its own opportunity is linked to its solicitation only when SAM.gov's award notice references that solicitation. awards(...) lists up to ten of the most recent linked awards; award_count is the full count.
• None of the new fields is in the SDK's default shapes (OPPORTUNITIES_MINIMAL / NOTICES_MINIMAL are unchanged), so callers name them in shape.

Testing

• uv run ruff format --check tango/, uv run ruff check tango/, uv run mypy tango/: clean.
• uv run python scripts/check_filter_shape_conformance.py: no errors.
• uv run python scripts/check_shape_coverage.py: no new drift.
• uv run pytest: 581 passed, 31 skipped. New tests/test_opportunity_awards.py covers shape validation for the new fields, response parsing on get_opportunity / list_notices, and that the two filters reach the request.

🤖 Generated with Claude Code