fix(cleanup): anchor cleanupPieces gate to last proving activity

[rvagg]

The permissionless gate was anchored to cleanup-mode entry, so the abandonment path took two INACTIVITY_WINDOWs (~60 days): a third party could delete an abandoned data set after 30 days but had to wait another 30 to clean up and collect the deposit. Both gates now share _withinActivityWindow, making delete and cleanup permissionless at the same moment. Deprecates the now-unused cleanupModeEpoch in place.

---

deleteDataSet becomes permissionless after INACTIVITY_WINDOW (~30 days) without proving activity, but cleanupPieces restarted that clock from the delete itself. The abandonment path therefore took ~60 days, and the cleanup deposit, meant as the bounty for whoever tears down an abandoned data set, was unclaimable by the deleter for a month and then up for grabs by anyone, breaking the incentive to do the (expensive) permissionless delete at all.

Fix: both functions now share one gate, _withinActivityWindow(), anchored to dataSetLastProvenEpoch (legacy fallback to LEGACY_ACTIVITY_EPOCH). That epoch is frozen once a data set enters cleanup mode (provePossession/nextProvingPeriod/addPieces all revert on deleted data sets), so a data set abandoned enough to delete is immediately cleanable by the same caller, while an actively-proving SP keeps its ~30-day exclusive cleanup window after a voluntary delete. The call ordering (delete, then cleanup) is unchanged: it's enforced by the CLEANUP_MODE_SENTINEL, which never depended on the removed anchor. cleanupModeEpoch is deprecated in place; _finalizeCleanup still clears v3.4.0 residue.

[Copilot]

Pull request overview

This PR fixes the cleanup incentive/abandonment flow by aligning the permissionless gate for cleanupPieces() with deleteDataSet(), both anchored to last proving activity rather than cleanup-mode entry. This ensures an abandoned data set can be deleted and cleaned up in the same sequence by the same caller, allowing the cleanup deposit bounty to be claimed immediately when appropriate.

Changes:

• Introduces _withinActivityWindow(setId) and reuses it for both deleteDataSet() and cleanupPieces() permission gating.
• Deprecates the old cleanup-mode anchor storage (cleanupModeEpoch) in-place (renamed to deprecatedCleanupModeEpoch) and clears any legacy residue during finalization.
• Expands cleanup-related test coverage to cover abandoned/active/legacy scenarios and storage-residue clearing.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
test/CleanupPieces.t.sol	Adds targeted tests verifying the new shared activity-anchored permission gate and legacy/residue behavior.
src/PDPVerifierLayout.sol	Renames the slot constant to reflect deprecated cleanup-mode epoch storage (same slot preserved).
src/PDPVerifierLayout.json	Renames the storage layout label to deprecatedCleanupModeEpoch to match the deprecation.
src/PDPVerifier.sol	Implements _withinActivityWindow and applies it to delete/cleanup gating; deprecates and clears the old gate anchor storage.
CHANGELOG.md	Documents the behavioral fix and the deprecation of cleanupModeEpoch.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[wjmelements]

Nice. Too bad we already deployed the cleanupModeEpoch.