Fixes TRST-M-1 audit finding:

Wrong TYPEHASH string is used for agreement updates, limiting functionality.

* Fixed EIP712_RCAU_TYPEHASH to use correct uint64 types for deadline and endsAt fields (was incorrectly using uint256)
* This prevents signature verification failures for RecurringCollectionAgreementUpdate

Fixes TRST-M-2 audit finding:

Collection for an elapsed or canceled agreement could be wrong due to
temporal calculation inconsistencies between IndexingAgreement and
RecurringCollector layers.

* Replace isCollectable() with getCollectionInfo() that returns both collectability and duration
* Make RecurringCollector the single source of truth for temporal logic
* Update IndexingAgreement to call getCollectionInfo() once and pass duration to _tokensToCollect()

Fixes signature replay attack vulnerability where old signed RecurringCollectionAgreementUpdate
messages could be replayed to revert agreements to previous terms.

 ## Changes

- Add `nonce` field to RecurringCollectionAgreementUpdate struct (uint32)
- Add `updateNonce` field to AgreementData struct to track current nonce
- Add nonce validation in RecurringCollector.update() to ensure sequential updates
- Update EIP712_RCAU_TYPEHASH to include nonce field
- Add comprehensive tests for nonce validation and replay attack prevention
- Add RecurringCollectorInvalidUpdateNonce error for invalid nonce attempts

 ## Implementation Details

- Nonces start at 0 when agreement is accepted
- Each update must use current nonce + 1
- Nonce is incremented after successful update
- Uses uint32 for gas optimization (supports 4B+ updates per agreement)
- Single source of truth: nonce stored in AgreementData struct

Implements slippage protection mechanism to prevent silent token loss
during rate-limited collections in RecurringCollector agreements.

The implementation uses type(uint256).max convention to disable slippage
checks, providing users full control over acceptable token loss during
rate limiting.

Resolves audit finding TRST-L-5: "RecurringCollector silently reduces
collected tokens without user consent"