MaintenanceUf2Repository
The pinned nRF52/RP2040 maintenance-UF2 manifest (factory-erase and OTAFIX bootloader self-update images), seeded from a bundled asset and refreshed from resource/maintenanceUf2. Each image's own sha256 is still checked against its downloaded bytes before any write — see MaintenanceUf2.kt — this repository only caches the manifest that names those images.