[mswilkison]

Maintains the ethers v5 release line as @threshold-network/hardhat-helpers@0.6.0-pre.22, starting from the fork's existing pre.21 tag. Includes upstream PR #56's hardhat-deploy 1.x peer support without rolling consumers back to pre.15.

The carried issues now have implementations for this release line:

• Make upgrade helpers optional for consumers that do not use proxies #2: /base loads and typechecks without the OpenZeppelin Upgrades plugin; /upgrades and the existing root entry enable proxy support. The plugin is an optional peer, and runtime dependencies are explicit.
• Support explicit repeat proxy deployment for isolated tests #3: deployProxy(..., { redeploy: true }) creates a fresh proxy and replaces the named record only after success. The duplicate guard remains the default.
• Add on-chain regression coverage for proxy upgrade helpers #4: on-chain deployment/upgrade tests cover initialization, retained storage, admin ownership, unauthorized upgrades, incompatible layouts, reverted calls, persisted receipts, and repeated deployments loaded from disk. Implementation addresses are read from ERC-1967 slots and the already-mined receipt is retained.
• Revalidate verification without recompiling deployment artifacts #5: require legacy etherscan 3.1.8+ and pass noCompile: true. Tests exercise deployed bytecode and the real task, with the explorer boundary mocked, and verify that contract/library/constructor inputs and artifacts are preserved.

The expanded suite also exposed an old unawaited time-helper assertion; it is now awaited and past-block errors are consistent. Generated fixture artifacts/manifests stay out of git.

Packaging includes compiled output, the new entry points, and migration documentation. CI covers the locked and deploy-v1 stacks, and the manual workflow builds release artifacts without publishing.

Validation:

• Node 16 / Hardhat 2.10 / ethers 5.6.9 / deploy 0.11.11 / Upgrades 1.22: typecheck, build, 55 tests.
• Node 24 / Hardhat 2.29 / ethers 5.8 / deploy 1.0.4 / Upgrades 1.28: typecheck, build, 55 tests.
• Frozen lockfile install, ESLint, Prettier, and npm pack passed.
• A clean Node 24 consumer installed the actual tarball, loaded named signers/block helpers, and typechecked without installing the optional Upgrades plugin.

The counterpart for ethers v6 is #7. Issues #2–#5 should close after both release-line PRs merge. Issue #1 concerns the v6 transaction adapter, which remains necessary even in current upstream OpenZeppelin code.

MIGRATION.md maps the hard package/import switch onto existing keep-core #4326, tbtc-v2 #1142, and solidity-contracts #193. Those PRs currently change manifest values only; release selection, import changes, and regenerated lockfiles remain consumer work. No package has been published by this PR.