Mitigate accepted V12 audit findings

[dangerousfood]

Summary

• align the Deepstate dependency lock metadata in the first commit
• preserve a final DEEP default admin and reject invalid admin handoffs
• bound Governor timing and fraction settings, enforce a quorum floor, and protect proposal admission at zero supply
• prevent STATE from becoming trapped in its own vault and require a six-decimal USDG value token
• add slippage-bounded ERC-4626 deposit/mint overloads while retaining the standard interfaces
• require per-token minimum outputs for listed-asset redemptions
• settle each rewarded side before an exhausted order book rotates, with an end-to-end historical-book claim test

Each accepted mitigation is isolated in one commit and labeled with its V12 finding ID. Findings addressed by one shared mechanism are grouped in that mechanism's commit.

Audit mapping

Finding	Mitigation
#227534, #227535	Align dependency metadata with the intended Deepstate commit
#227408	Prevent revocation or renunciation of the final DEEP default admin
#227513	Require one past vote to propose when historical supply is zero
#227514	Cap voting delay at 30 days
#227515	Cap late-quorum extension at 7 days
#227516	Cap voting period at 30 days
#227517	Floor quorum at 1 STATE
#227518	Require at least a 1-day voting delay
#227519, #227520, #227522	Reject zero proposal and quorum fractions
#227523	Reject nonzero STATE transfers or mints to the vault itself
#227527	Require a six-decimal vault value token
#227528	Add bounded deposit and mint entry methods
#227529	Add per-asset minimums to listed redemption and disable the unsafe overload
#227435	Close rewarded book cursors before rotation

The #227435 engine change is implemented in Deepstate-Protocol/deepstate-contracts#33 and pinned here at 59e5bb25a023d96a50a78fb1bd8504b5aa8e14ad.

Validation

• forge fmt --check
• forge build --sizes --threads 0
• 129 behavioral and fuzz tests passed
• five reward invariants passed across 640,000 transitions with zero reverts
• DeepstateVault coverage: 100% lines (156/156), statements (207/207), branches (39/39), and functions (28/28)
• dependency suite: 435 tests passed, including 49,152 updated multi-pool invariant calls with zero reverts