Add a generic conditional-pricing mechanic: a ProductPrice may carry
meta.requires (e.g. {"role":"seat"}) so it only applies to buyers who
already hold a prerequisite (loyalty / bundle pricing). Product::resolvePriceFor
returns the cheapest price the buyer is eligible for, delegating the
'does the buyer satisfy this requirement' test to a host-bound
EntitlementChecker contract. Defaults to DenyAllEntitlementChecker so an
unconfigured host never leaks a discount. Adds requires()/isConditional()/
requiresLabel()/requiresSatisfiedBy() and conditional()/standalone() scopes.
- Added strict types declaration to multiple traits for better type safety.
- Updated method signatures in traits to use nullable types where applicable.
- Improved documentation for traits, including host-model contracts and method descriptions.
- Added new tests to ensure correct behavior of loan checkout and stock management.
- Fixed regression in order number generation to ensure proper string formatting.
- Ensured that currency codes sent to Stripe are consistently lowercased.
Fabian @ Blax Software