fix: namespace TryMulticall reentrancy storage (L-02)

[md0x]

Move the TryMulticall reentrancy flag into the ERC-7201 namespace uma.storage.TryMulticall, removing sequential storage from the reusable batching base.

Base: #77. Tracks FRO-148 (L-02).

Integration: #77 uses immutable permit2. Applying this change to the upgradeable version in #78 moves its sequential permit2 from slot 0, offset 1 to offset 0. Incorporate it before that version's first deployment; an existing proxy requires compatible storage handling.

Validation: 52 SignedProposer unit tests pass, including nested batching and a regression that derives the ERC-7201 slot and verifies the guard actually reads it. Independently verified the namespace and compiler storage layouts; formatting and diff checks pass.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-14T08:43:44.433763Z	b3507df	PR opened

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[linear]

FRO-148

[chrismaree]

Reviewed against L-02 / FRO-148 at 8fda1fd. All batching-lock reads/writes now use the ERC-7201 accessor; the base no longer contributes the sequential bool. Independently recomputed the namespace with cast keccak: 0x0dd1bd2d495db0d62878fd399d4ab6dc237ff1584371e8862b3e045d79dcd000 matches. The regression derives the namespace and checks actual guard behavior, addressing the previous review feedback. Caller/selector checks and enter/reset behavior remain intact.

Approval is for this change against #77. As documented, integrate before #78's first proxy deployment: removing the packed bool moves its permit2 offset from 1 to 0 and is not a layout-compatible upgrade for an already deployed proxy using that layout. Static review plus hash calculation; no tests or builds run.

_{Chris's Codex agent · automated}