[Nic-dorman]

Part of the sha-fanout round (V2-1724): the SDK side of the sha256 fields antd 0.17.0 added in #347. Targets main; the daemon and antd-go are already released.

antd 0.17.0 returns the plaintext's SHA-256 (lowercase hex) on every upload
response and lets a manifest entry carry one (V2-1724).

Upload results: DataPutResult, DataPutPublicResult, FilePutResult,
FilePutPublicResult, FinalizeUploadResult and FinalizeMerkleUploadResult
gain sha256: String?. A missing key (antd < 0.17.0, REST) or an empty
string (gRPC's zero value) reads as nil. POST /v1/data, /v1/data/public,
/v1/files, /v1/files/public and /v1/upload/finalize (wave and merkle) are
mapped on both transports.

Manifests: ManifestEntryInput gains sha256: String?, sent only when set
and non-empty (omitted from the REST JSON; proto3 optional presence left
unset over gRPC). ManifestEntryInfo gains sha256: String?, nil when absent
or empty, on build and decode. The hash is passed through as given: no hex,
length or case check, so a malformed one is the daemon's 400 /
INVALID_ARGUMENT as BadRequestError with the server's message.

Compatibility: every new initializer parameter is last with a default of
nil, so existing construction compiles unchanged. No protocol requirement,
error type or enum changed. No fluent helper (no withSize siblings). No
generated stub changed: the committed ones already carry the fields.
Requires antd 0.17.0 or later; README documents it.

Tests: 12 new unit tests (6 REST over StubURLProtocol, 6 in-process gRPC)
cover presence, absence and empty on each result type, the manifest request
JSON / proto presence, build and decode reads, and the 400 mapping. A
gated live test (LiveSha256Tests, ANTD_TEST_URL / ANTD_TEST_GRPC plus
ANTD_TEST_SHA_LINK) decodes the fixture link, builds with and without a
hash, expects the bad-request error for "zz", and makes one paid public data
upload per transport, checking the returned sha256 against a local SHA-256
(self-contained implementation, no new dependency). Run against antd 0.17.0
on a local devnet: rest 306a7998...facb62 and grpc 7efecabe...ef196f both
matched. Full suite 185 tests, 5 skipped (live), 0 failures, on Swift 6.1.3.

🤖 Generated with Claude Code

[MaidSafe-Hermes]

APPROVE — reviewed head a8a7766c7281e470789b65f2193ded1b84a40580.

Coverage: 2/2 seats reviewed (sol-1 gpt-6.1-sol xhigh; glm-1 z-ai/glm-5.3). Sol-1 raised a Swift 6 asynchronous locking concern; the exact-head macOS Build + test CI check passes, resolving that compile concern for the configured toolchain.

REST/gRPC upload results normalize absent/empty hashes; manifest inputs omit unset/empty values and outputs read the optional field. Tests cover these paths, and CI reports build and test success. Live devnet behavior was not independently rerun here. This is a code-review approval only; no merge performed.