SubAccount V2 (3/3): rust-sdk V2 + SDK integration tests

[santy311]

Summary

The rust-sdk V2 sub-account API and its SDK-level integration tests. (The interface builders these depend on live in #188.)

rust-sdk

• types::Permission: five V2 variants (Create + scoped All/Sign/Withdraw/Toggle) with to_client_actions / from_role / to_action_type.
• ClientRole: four V2 methods (create/sign/withdraw/toggle) with default "unsupported" impls, overridden for Ed25519, Secp256k1, Secp256r1, and the three session variants (which delegate to the Ed25519 builders via the session key). Secp256k1/r1 thread the odometer as the replay counter. ProgramExec uses the default impl.
• SwigInstructionBuilder + SwigWallet: V2 create/sign/withdraw/toggle, a counter reader, and get_sub_account_v2. Create reads the on-chain counter to derive the next sub-account's PDAs.

tests (rust_sdk_test)

Thirteen SDK integration tests via the SwigWallet API:

• lifecycle — create/counter, sign + SOL withdraw, Ed25519 token withdraw, toggle kill-switch
• validation — state account pre-funded but uninitialized, invalid enabled wire byte
• authorization — All alone cannot create (default-deny)
• Secp256k1 / Secp256r1 — k1 sign, and k1 + r1 create followed by token withdraw
• sessions — Ed25519 session create + SOL withdraw, token withdraw, and toggle

Test

cargo build-sbf --arch v1
cargo test -p swig-sdk --features rust_sdk_test sub_accounts_v2_test   # 13
cargo test -p swig-sdk --features rust_sdk_test                        # 135

Stack

1. SubAccount V2 (1/3): state-crate data model #187 — state data model (base main)
2. SubAccount V2 (2/3): program + interface builders + program tests #188 — program + interface builders + program tests (base SubAccount V2 (1/3): state-crate data model #187)
3. this PR — rust-sdk V2 + SDK integration tests (base SubAccount V2 (2/3): program + interface builders + program tests #188)

🤖 Generated with Claude Code

[santy311]

Stacked PRs — review/merge bottom → top:

1. SubAccount V2 (1/3): state-crate data model #187 — state data model (base main)
2. SubAccount V2 (2/3): program + interface builders + program tests #188 — program instructions + handlers (base SubAccount V2 (1/3): state-crate data model #187)
3. SubAccount V2 (3/3): rust-sdk V2 + SDK integration tests #189 — rust-sdk + interface + tests (base SubAccount V2 (2/3): program + interface builders + program tests #188)

[tracy-codes]

The "known gaps" part of the PR seems outdated. sub-accounts_v2_test at line 311 and 368 both create and withdraw with Secp256k1/r1. It also says 5 tests but there's 9.

There's no session authority tests, which we need to have for coverage.