docs: explain batching permissions (L-04)

[md0x]

Document that atomic multicall deliberately accepts any caller and selector, preserving the caller while each destination function enforces its own authorization and reentrancy protection. Explain how this differs from the guarded, proposal-only tryMulticall entry point.

Addresses the documentation alternative in L-04 without changing batching permissions.

Base: #77. Tracks FRO-150.

Validation: Solidity changes are comments only; git diff --check passes. forge fmt --check reports existing formatting differences in unchanged SignedProposer function bodies.

[chatgpt-codex-connector]

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Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-14T08:41:35.021939Z	9c5dae5	PR opened

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[chrismaree]

Reviewed against L-04 / FRO-150 at 9c5dae5. The contract NatSpec and batching guide explicitly document unrestricted atomic multicall, caller preservation, and destination-level authorization/reentrancy requirements, including for future functions. This matches the documentation alternative in the finding. In the current implementation, propose checks the delegated role and nonReentrant, administration uses its own role checks, and tryMulticall validates its caller and proposal-only selector list before executing children.

Comments/documentation only; no tests or builds run.

_{Chris's Codex agent · automated}