Migrate to the compiler-derived candidate source anchor: rain-deploy removes DeployCandidate.sourceCreationCode

[thedavidmeister]

Upstream change

rainlanguage/rain.deploy#242 removes DeployCandidate.sourceCreationCode and
makes checkCandidatesAnchoredToSource resolve the candidate's own
snapshot.artifactPath through vm.getCode instead. The source operand now
comes from the compiler rather than from the declaration, so a consumer names
the contract and has no say in what that contract compiles to.

This repo is the one that found the bug: #34, whose mutant M27 flipped
sourceCreationCode from type(CloneFactory).creationCode to the recorded
constant and survived this repo's whole 28-test suite. #242 closes it.

This is a BREAKING change and every declaration in this repo must be edited
before the pin can move.

What this repo has to change

Current pin: "rain-deploy" = "0.1.8" (foundry.toml:45).

1. src/abstract/CloneFactoryDeploySuites.sol

One candidate, clone-factory:

• Line 56 — delete sourceCreationCode: type(CloneFactory).creationCode,
  and the trailing comma on the snapshot: DeploySuite({...}) entry above it.
  The DeployCandidate({...}) literal is left with its single snapshot field.
• Line 6 — delete import {CloneFactory} from "../concrete/CloneFactory.sol";.
  It becomes unused: line 56 is its only use. The other CloneFactory spellings
  in this file are the aliased import from ../generated/candidate/CloneFactory.sol
  (line 10) and doc prose, neither of which needs the type.

artifactPath at line 53 is "src/concrete/CloneFactory.sol:CloneFactory".
Checked against the tree: src/concrete/CloneFactory.sol exists and declares
contract CloneFactory, so it resolves and needs no correction. Note that after
#242 this string stops being a forge verify-contract convenience and becomes
the load-bearing source operand — the anchor fails, inside
RainDeployBroadcast.run() and before the broadcast, if it ever goes stale.

2. script/Build.sol

• Line 88 — contracts[i].candidate.sourceCreationCode, becomes
  vm.getCode(contracts[i].candidate.snapshot.artifactPath),, so
  regenerateSnapshots writes from the same origin the anchor reads back.
• Line 18 — the GeneratedContract doc comment says "Snapshots are written
  from its sourceCreationCode and snapshot.dependencies"; that field will no
  longer exist.

3. Version pin, when there is one to move to

Seven files spell the versioned remapping prefix rain-deploy-0.1.8/ and each
has to be rewritten together with foundry.toml and soldeer.lock:

• src/abstract/RainDeploySuitesBase.sol (the re-export shim that holds the one
  local spelling of the package path — but which the generated libs reach
  through a relative import, so it cannot be skipped)
• script/Build.sol, script/Deploy.sol
• test/src/abstract/CloneFactoryDeployChain.t.sol,
  test/src/abstract/CloneFactoryDeploySnapshot.t.sol,
  test/src/lib/LibCloneFactoryDeployCandidate.t.sol,
  test/src/lib/LibCloneFactoryDeploy.t.sol

Related but separate

#41 — the RECORD half of the anchor can still be spelled
type(X).creationCode. #242 explicitly does not close that, and this issue does
not either.

The version to bump to does not exist yet

rainlanguage/rain.deploy#242 is open, unmerged and unreleased. There is no
published rain-deploy version carrying this change, so this issue deliberately
names none. The bump target has to be filled in once #242 merges and a Soldeer
release is cut; until then this issue is the record of what the edit will be,
not a request to make it.

Not affected in this repo

Migration item 3 of #242 — "any consumer wrapper marked pure must become
view" — needs no edit here. This repo inherits RainDeployVerifySnapshot
without redeclaring testSnapshotMatchesSource or wrapping
checkCandidatesAnchoredToSource, so the mutability change lands entirely
inside the package.

Migration item 4 — no foundry.toml change is required, because vm.getCode
does not go through fs_permissions.