Implement FIN-WP-0001 ledger, evaluate, and evidence lane (T03–T05)

Add SQLite-backed cost ledger with import/summary CLI, cron-friendly
evaluate command with federation emit, and dogfood evidence artefact
generation from fixture CSVs.

src/fin_hub/services/evaluate.py

@@ -0,0 +1,56 @@
+"""Scheduled runway evaluation from ledger data."""
+
+from __future__ import annotations
+
+import json
+from pathlib import Path
+
+from fin_hub.coupling.canon import emit_viability_alert
+from fin_hub.coupling.dev_hub import emit_resource_pressure
+from fin_hub.services.alerts import evaluate_budget_alerts
+from fin_hub.services.ledger import get_opening_balance, monthly_burn_series
+from fin_hub.services.runway import compute_runway
+
+
+def evaluate_runway(
+    *,
+    ledger_path: Path,
+    opening_balance: float | None = None,
+    alert_threshold_months: float = 3.0,
+    currency: str = "EUR",
+    allocated: float | None = None,
+    spent: float | None = None,
+    emit: bool = False,
+    api_base: str | None = None,
+) -> dict:
+    stored_balance, stored_currency = get_opening_balance(ledger_path)
+    balance = opening_balance if opening_balance is not None else stored_balance
+    if balance is None:
+        raise ValueError("opening balance required — use ledger set-balance or --balance")
+
+    effective_currency = currency or stored_currency
+    burns = monthly_burn_series(ledger_path=ledger_path, currency=effective_currency)
+    runway = compute_runway(
+        current_balance=balance,
+        monthly_burns=burns,
+        alert_threshold_months=alert_threshold_months,
+        currency=effective_currency,
+    )
+    alerts = evaluate_budget_alerts(runway=runway, allocated=allocated, spent=spent)
+
+    report: dict = {
+        "runway": runway.as_dict(),
+        "alerts": [alert.as_dict() for alert in alerts],
+        "monthly_burns": burns,
+        "ledger_path": str(ledger_path.resolve()),
+    }
+
+    if emit:
+        report["dev_hub"] = emit_resource_pressure(alerts, api_base=api_base)
+        report["canon"] = emit_viability_alert(runway, api_base=api_base)
+
+    return report
+
+
+def evaluate_runway_json(**kwargs) -> str:
+    return json.dumps(evaluate_runway(**kwargs), indent=2, default=str)