Add USAspending/SAM.gov/Grants.gov procurement CLI

Goal

Add a Printing Press CLI for public procurement, grants, awards, and vendor intelligence.

Free source

• USAspending.gov API.
• SAM.gov APIs where available.
• Grants.gov data/API surfaces.

Agent jobs

• Research government spend by agency, vendor, category, and time period.
• Find active opportunities and grants.
• Track vendor/competitor public-sector footprint.

Proposed command shape

• govspend-pp-cli vendor "Palantir" --agent
• govspend-pp-cli agency "NASA" --since 1y --agent
• govspend-pp-cli opportunities --query "cybersecurity" --agent
• govspend-pp-cli grants --query "climate" --agent
• govspend-pp-cli awards --naics 541511 --agent

Non-goals

No bidding, submission, login-gated workflows, or compliance advice.\n\n## Implementation path\n\nThis is a new CLI candidate, so do not hand-build it directly in this published library repo. Run it through the canonical Printing Press generation flow in cli-printing-press, keep manuscripts/proofs, then publish into this repo with the publish flow.\n\n## Acceptance criteria\n\n- Research notes explain the source/API/feed contract, rate limits, auth needs, and freshness behavior.\n- CLI exposes a small agent-native command set, not a raw endpoint dump.\n- --json / --agent output is stable and compact.\n- If the source benefits from history, add local SQLite sync plus since/diff commands.\n- Skill includes high-signal recipes and clear non-goals.\n- Dogfood proves at least three realistic agent workflows.