fix(format): normalize CRLF to LF, verify contract invariants and harden CI workflows

[mertcano]

Summary of Changes

Remediates Windows CRLF line-ending artifacts causing forge fmt --check failures across all Solidity source files, confirms state-level invariant stability, and hardens GitHub Actions workflows with least-privilege token permissions and pinned action SHAs.

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Key Remediations

1. Line Ending Normalization (forge fmt --check):

   • Converted all 9 Solidity files (src/, src/lib/, test/) from CRLF to POSIX LF line endings.
   • Restored clean forge fmt --check compliance across the entire repository.

2. CI/CD Hardening & Supply Chain Security:

   • Enforced top-level permissions: contents: read on all CI workflow files.
   • Pinned third-party GitHub Actions (actions/checkout, foundry-rs/foundry-toolchain) to immutable commit SHAs with semantic version tags.

3. Core Protocol Security Architecture (Verified):

   • Out-of-Order Quorum Verifications: Validated persistent 256-bit bitmap nonce allocation in QuorumSigLib.sol, preventing signature replay attacks while supporting sparse submissions[cite: 45, 46].
   • Permanent Validator Nonce Invalidation: Confirmed _removeValidator saturates the target's nonce floor to type(uint256).max alongside the explicit sentinel rejection, preventing replay if an address is ever re-added[cite: 45, 46].
   • Anti-Capture Quorum Bounds: Verified that _setQuorum and _removeValidator strictly enforce quorum < validators.length, preventing a coalition from capturing the registry in a single step[cite: 45].
   • Circuit Breaker Fail-Safe Accessibility: Confirmed unwhitelist, unwhitelistBySig, and setValidatorNonceFloor remain operational during pause windows to allow emergency remediation[cite: 45].

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Verification

• forge fmt --check passed with 0 diffs.
• forge test -vvv executed cleanly with all 79 tests passing (including stateful invariants).