Refresh S3 carrier for native v49

[theysayheygreg]

Summary

• identify the merged S3 target as fleet hardware family 2
• embed the exact native-v49 propagating Dig2Go and ordinary Athom C3 payloads in the S3 carrier vault
• seed the existing fleet update offer from the S3 target without adding a new protocol
• keep S3 excluded as a propagation receiver

Verification

• all four delivery environments build at exact commit 321fa8d8
• S3 carrier contains family 1 / family 3 payloads plus its own family 2 v49 identity
• carrier runtime contracts: 10/10
• vault validator: 2/2
• fleet protocol C++ test passes
• carrier artifact SHA-256: 57523b06edfc39453821cf7f1d2598564a375333c05f610ee06aaad4aa6f158b

This is the narrow downstream refresh after merged PRs #71 and #72; it does not change the peer protocol or public Easy Flash UI.