[IMP][P1] Hourly tracking: env-gated Postgres read tools

[mishrapravin114]

Type

Implementation — merge a PR with working code. Not investigation.

Goal

Replace hardcoded mock data in hourly_tracking/tools.py with env-gated read-only Postgres queries for finance pilot demos.

Files to change

examples/templates/hourly_tracking/tools.py ← UPDATE
examples/templates/hourly_tracking/.env.example ← NEW
examples/templates/hourly_tracking/README.md ← UPDATE (Production wiring section)

Implementation checklist

• When HOURLY_TRACKING_USE_LIVE=1 and CLIENT_DB_URL set: run read-only SQL for broker + investor feeds
• When unset: keep current mock behavior (CI + demos still work)
• Use stdlib or existing deps only — do not add new dependencies without approval
• Parameterized queries only; no string interpolation of user input
• ./engine validate examples/templates/hourly_tracking passes
• ./engine run examples/templates/hourly_tracking --input '{}' works with mocks

SQL sketch (implement in tools.py)

-- broker transactions last hour (read-only user)
SELECT transaction_id, broker_id, investor_id, input_amount, output_amount, fees
FROM broker_transactions
WHERE created_at > now() - interval '1 hour';

Done when

• PR merged
• README shows mock vs live toggle
• .env.example documents CLIENT_DB_URL, HOURLY_TRACKING_USE_LIVE

Out of scope

• Client-specific schema migration
• Write access to client DB

Related (context only)

#15 Section 2.4 hourly_tracking example · Closed #2