8.9.1 / 2024-12-16

• fix(connection): remove heartbeat check in load balanced mode #15089 #15042 #14812
• fix(discriminator): gather childSchemas when creating discriminator to ensure $getAllSubdocs() can properly get all subdocs #15099 #15088 #15092
• fix(model): handle discriminators in castObject() #15096 #15075
• fix(schema): throw error if duplicate index definition using unique in schema path and subsequent .index() call #15093 #15056
• fix: mark documents that are populated using hydratedPopulatedDocs option as populated in top-level doc #15080 #15048
• fix(document+schema): improve error message for get() on invalid path #15098 #15071
• docs: remove more callback doc references & some small other changes #15095