create WritableFreezeStore for SwirldDualState data

### Problem

FreezeService.handle needs access to SwirldDualState in order to read and write the freezeTime. SwirldDualState is currently not accessible from the modularized codebase.

### Solution

Create a WritableFreezeStore class. It should be a wrapper around the DualState interface. It will have freezeTime and lastFrozenTime fields getters/setters. It receives a DualState when it's constructed and it just calls through.

We only need a WritableFreezeStore, not a ReadableFreezeStore, because preHandle does not need access to this data, only handle. However we might want to create a ReadableFreezeStore for consistency with the other stores.

Create this store interface in the spi module. Unlike other stores, it is not defined as part of a module but defined as part of an spi. Any service could use this but they shouldn't, only FreezeService needs it. Implementation rests with HederaApp, not in a module. It's up to HederaApp to make sure that it's on the right version of the merkle tree.

Relies on issue #4211 before FreezeService can access this new store from outside its module.

### Alternatives

_No response_

Start by reading the DualState interface, FreezeService.handle, the spi module, and HederaApp, while checking the dependency on issue #4211. Define the WritableFreezeStore in spi with delegated freezeTime and lastFrozenTime access, then ensure HederaApp supplies the appropriate DualState version for FreezeService.

Written by the indexing model from the issue text.