M1: persistent vault, local unlock key, sync client, test vectors

kv-store: SQLite (bundled) and in-memory Store holding only ciphertext
envelopes, with base copies for three-way merges and a 10-version history.

kv-ffi: VaultCore::open(path); persisted account record; local unlock key
(enable/unlock_with_local_key/disable); async sync API (configure_server,
set_device_signer, register_account, login, sync_now, logout, devices);
DeviceSigner foreign trait; IntegrityAlarm/PinMismatch/... error variants.

kv-sync: reqwest + rustls (TLS 1.3 only, ring) with SPKI pinning; OPAQUE
client on kv-proto's OpaqueSuite; RFC 9421 signing per kv_proto::httpsig;
pull/push with If-Match, field-level three-way merge, edit-beats-delete;
signed manifest (canonical CBOR, Merkle root, prev chain, Ed25519) with
rollback/fork/Merkle checks as hard integrity alarms. Tested against a
wiremock fake server, plus an #[ignore] test against kestrove-server.

kv-crypto: gen-vectors example and tests reproducing kestrove-spec/vectors.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

Cargo.toml

@@ -37,6 +37,21 @@ data-encoding = "2"
 url = "2"
 psl = "2"
 uniffi = "0.28"
+rusqlite = { version = "0.32", features = ["bundled"] }
+opaque-ke = { version = "3", features = ["std"] }
+reqwest = { version = "0.12", default-features = false, features = ["json", "rustls-tls-manual-roots-no-provider", "http2"] }
+rustls = { version = "0.23", default-features = false, features = ["ring", "std", "tls12", "logging"] }
+webpki-roots = "0.26"
+rustls-webpki = { version = "0.103", default-features = false, features = ["alloc", "ring"] }
+tokio = { version = "1", features = ["rt-multi-thread", "macros", "time", "sync", "net", "io-util"] }
+ciborium = "0.2"
+blake3 = "1"
+p256 = { version = "0.13", features = ["ecdsa", "pkcs8"] }
+time = { version = "0.3", features = ["formatting"] }
+wiremock = "0.6"
+rcgen = "0.13"
+tokio-rustls = { version = "0.26", default-features = false, features = ["ring", "tls12"] }
+tempfile = "3"
 
 [profile.release]
 lto = true