chore: update contract migrations after 3.14 release

[gilcu3]

Closes #4080

[claude]

Pull request overview

Routine post-release migration cleanup: the 3.13.0 state shadow is replaced by a 3.14.0 one, and the archived "production" contract binary rolls forward to signer-3_14_0.wasm. Because nothing in MpcContract's borsh layout has changed since the 3.14.0 release cut (#4060 merged 2026-08-05 09:47Z; no PR touching crates/contract/src has landed since), the new shadow can reuse the live types verbatim and the migration becomes an identity conversion. The launcher-expiry and legacy-mock stamping steps that shipped in 3.14.0 are dropped along with the old module, which also removes the last TODO(#3978) reference.

Changes:

• Adds crates/contract-history/archive/signer-3_14_0.wasm (1 187 525 B) and version_3_14_0(); repoints current_mainnet()/current_testnet() at it.
• Deletes v3_13_0_state.rs (incl. OldConfig/OldTeeState/OldAllowedLauncherImage shadows, stamp_expiry_on_legacy_mocks, and their unit tests); adds v3_14_0_state.rs as a field-for-field identity shadow; migrate() now reads the 3.14.0 shadow.
• Drops the now-unused migration constructor AllowedLauncherImages::from_entries.
• Trims 3.13.0-specific comments from the sandbox upgrade test.

Reviewed changes

Per-file summary

File	Description
crates/contract-history/archive/signer-3_14_0.wasm	New archived production binary (sha256 c64ecba1…7422). The ~322 KB drop vs 3.13.0 is consistent with #3714 dropping dcap-qvl.
crates/contract-history/src/lib.rs	Adds version_3_14_0(); current_mainnet()/current_testnet() now return it.
crates/contract/src/lib.rs	pub mod v3_14_0_state; migrate() reads the 3.14.0 shadow and logs against it.
crates/contract/src/tee/proposal.rs	Removes AllowedLauncherImages::from_entries (only caller was the deleted migration; verified no remaining references).
crates/contract/src/v3_13_0_state.rs	Deleted — shadow types, stamp_expiry_on_legacy_mocks, and three unit tests.
crates/contract/src/v3_14_0_state.rs	New shadow: 14 fields in the same order/types as crate::MpcContract (lib.rs:167-191), identity From impl guarded on Running.
crates/contract/tests/sandbox/upgrade_to_current_contract.rs	Comment-only: de-versions the launcher-hash setup/assert comments.

Verified locally: shadow field list and order match crate::MpcContract exactly; every import in the new module is used; AllowedLauncherImage::new, with_expiry_capped_at, current_time_seconds, and the test helpers used by the deleted tests all retain other callers, so no dead code is left behind. Cargo test: contract (which runs -p mpc-contract, including sandbox::upgrade_to_current_contract) is green on this PR, so the 3.14.0 → HEAD upgrade path — with a non-empty launcher entries vec — is exercised.

Findings

Blocking (must fix before merge):

• crates/contract-history/src/lib.rs:1-7 — Confirm 3.14.0 is actually the code deployed at v1.signer and v1.signer-prod.testnet before merging. current_mainnet()/current_testnet() are asserted against the on-chain code hash by mainnet_contract_should_be_up_to_date/testnet_contract_should_be_up_to_date (lib.rs:83-99), but that workflow only triggers on push: main, tags, schedule and dispatch (.github/workflows/external-services-tests.yml:8-14), so no check on this PR covers the claim. The timing is what makes it worth pausing on: the release landed 2026-08-05 and this PR is dated 2026-08-06, whereas the analogous 3.13.0 cleanup (chore(contract): cleanup migrations after 3.13.0 release #3771) landed 16 days after that release. If either network is still on 3.13.0, then (a) the external-services job goes red on main right after merge, and (b) deleting v3_13_0_state removes the only path off 3.13.0 — a network upgrading straight from 3.13.0 to the next release would fail both branches in migrate() and hit env::panic_str at crates/contract/src/lib.rs:2139, reverting the deploy until the shadow is restored. If deployment on both networks is confirmed done, this is a non-issue and the rest of the PR looks correct.

Non-blocking (nits, follow-ups, suggestions):

• docs/design/auto-remove-launcher-hashes-design.md:124-128 — The ## Migration section still describes the migration this PR deletes ("existing entries get expires_at = migration time + TTL … The 3.13.0 migration also stamps an expiry on legacy MockAttestation::Valid entries"). Per CLAUDE.md §Documentation alignment, mark it as historical in the same PR, e.g. "Shipped in 3.14.0; the migration code was removed in chore: update contract migrations after 3.14 release #4081."
• crates/contract/src/tee/proposal.rs:376-377 — The tie example on latest_expiry_index ("e.g. right after a migration stamps every entry with the same expires_at") now refers to code that no longer exists. Ties are still reachable (two hashes voted in within the same block, since expiry_from_now derives from Timestamp::now()), so just re-point the example.
• crates/contract/src/v3_14_0_state.rs:32 — "see this module's history for examples" won't resolve: the examples live in the deleted v3_13_0_state.rs, and the add+delete pair is far below git's rename-similarity threshold (432 → 75 lines), so git log --follow on this path shows nothing. Reference the deleted file or this PR instead.
• PR body — TODO(#3978) was the only reference to issue Remove the legacy-mock expiry-stamping migration once it is superseded #3978 ("Remove the legacy-mock expiry-stamping migration once it is superseded"), which is still open and is exactly what this PR does. Consider adding Closes #3978 alongside Closes #4080.

⚠️ Issues found

[anodar]

Thanks!