snow_rendering 0.2.0

Weather-to-rendering computation for driving safety applications. Road surface classification, precipitation particle parameters, and visibility degradation derived from weather data. Pure Dart — no F [...]

0.2.0

• Add DataBudget — stateful data-fetch budget tracker for snow- overlay render bandwidth management. Integrator-supplied DataMeterProvider interface; per-cycle bytes budget checked against DataBudgetConfig; broadcast budgetEvents stream emits BudgetWarning (75%) / BudgetExhausted (100%) / RenderFidelityDrop (in lock-step with Exhausted). Mirrors the GlanceBudgetTracker pattern from navigation_safety 0.9.0 (caution-add-only / severity-not-profile / driver-always-drives invariants enforced via debug-mode runtime asserts).
• Add DataBudgetConfig.forProfile(DriverProfile) factory — per- cohort tighter-direction defaults (4MB baseline / 3MB noviceUrban / 2MB ageingRural + foreignTouristSnowZone for bandwidth-margin). Per-cohort budgets are UNVERIFIED-magnitude design-default- hypothesis pending field-measurement validation; conservative-only (every cohort <= 4MB baseline). Per-population calibration deferred.
• Add tighten(int) — auto-tightening allowed at runtime; new budget must be <= active budget per caution-add-only invariant.
• Add relax(int, BudgetRelaxConfirmation) — auto-relax FORBIDDEN; loosening requires integrator-supplied affirmative confirmation token. Mirrors the cap-override-with-confirmation pattern from navigation_safety_core 0.10.0 #30 (driver-always-drives).
• Add BudgetResetReason enum + DataFetchEvent value object + sealed DataBudgetEvent hierarchy.
• Add navigation_safety_core: ^0.10.0 dependency for DriverProfile consumption.
• Add SAFETY_BOUNDARY.md (DataBudget invariants; cohort-tighter direction caveat; auto-relax-with-confirmation pattern; ASIL-QM advisory; severity-not-profile + driver-always-drives preserved).
• Add KNOWN_LIMITATIONS.md (per-cohort data-budget UNVERIFIED- magnitude flags + bandwidth-class assumptions).
• Public API additions are non-breaking; existing DrivingConditionAssessment / RoadSurfaceState / PrecipitationConfig / VisibilityDegradation contracts unchanged.

0.1.0

• Initial extraction from driving_conditions (SNGNav P1, D-SC22-2).
• RoadSurfaceState — six-state road surface classification with grip factors.
• PrecipitationConfig — particle configuration derived from weather conditions.
• VisibilityDegradation — opacity and blur parameters from visibility distance.
• DrivingConditionAssessment — combined assessment with advisory message.
• HysteresisFilter<T> — debounce filter for state oscillation at boundary conditions.