Fakes should support workflows with generated bindings

[ernest-nowacki]

Description

cre workflow simulate (cre-cli) writes Solana reports through the mock forwarder fake in contracts/capabilities/fakes. Workflows built with SDK-generated bindings (Go cre-sdk-go, TS @chainlink/cre-sdk) construct reports for production:

• remainingAccounts layout: index 0 = forwarder state, index 1 = forwarder authority PDA, index 2+ = receiver accounts — taken from workflow config, i.e. the real keystone forwarder;
• report embeds account_hash = sha256(concat(remainingAccount pubkeys)), which the forwarder recomputes on-chain over [state, authority, ...remaining] and rejects on mismatch (Custom:6002 InvalidAccountHash).

Since the fake substitutes the mock forwarder's state/authority, the workflow-computed hash never matches and every simulated write fails with InvalidAccountHash.

This PR makes FakeSolanaChain.WriteReport accept unmodified production reports:

1. strips remainingAccounts[0..1] (forwarder state + authority), mirroring the real transmitter's forwarder_client.go, which maps them onto named instruction accounts;
2. rewrites account_hash in place over the account list the mock forwarder will actually see: [mock state, mock authority, ...receiver accounts] (patchReportAccountHash). Safe because the mock forwarder verifies no DON signatures and the transaction is signed by the fake's transmitter afterwards;
3. logs info whenever the hash is rewritten.

Net effect: workflows keep their production config — no simulation-specific forwarder addresses, no binding changes, cre workflow simulate and deploy use identical workflow code.

Also adds contracts/capabilities/fakes/README.md documenting the mock-forwarder write path and what receiver authors still need (receiver's own caller validation must accept the mock forwarder).

Testing: TestPatchReportAccountHash covers hash rewrite, idempotent no-op on second patch, and too-short raw report error. Verified end-to-end via cre workflow simulate on solana-devnet against a bindings-based workflow (sol_cap-canary equivalent).

Requires Dependencies

Resolves Dependencies

• I will create cre-cli PR that would bumps github.com/smartcontractkit/chainlink-solana/contracts to this commit; once it lands indevelop.

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📊 API Diff Results

No changes detected for module github.com/smartcontractkit/chainlink-solana/contracts

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