* all: implement path-based state scheme
* all: edits from review
* core/rawdb, trie/triedb/pathdb: review changes
* core, light, trie, eth, tests: reimplement pbss history
* core, trie/triedb/pathdb: track block number in state history
* trie/triedb/pathdb: add history documentation
* core, trie/triedb/pathdb: address comments from Peter's review
Important changes to list:
- Cache trie nodes by path in clean cache
- Remove root->id mappings when history is truncated
* trie/triedb/pathdb: fallback to disk if unexpect node in clean cache
* core/rawdb: fix tests
* trie/triedb/pathdb: rename metrics, change clean cache key
* trie/triedb: manage the clean cache inside of disk layer
* trie/triedb/pathdb: move journal function
* trie/triedb/path: fix tests
* trie/triedb/pathdb: fix journal
* trie/triedb/pathdb: fix history
* trie/triedb/pathdb: try to fix tests on windows
* core, trie: address comments
* trie/triedb/pathdb: fix test issues
---------
Co-authored-by: Felix Lange <fjl@twurst.com>
Co-authored-by: Martin Holst Swende <martin@swende.se>
The state availability is checked during the creation of a state reader.
- In hash-based database, if the specified root node does not exist on disk disk, then
the state reader won't be created and an error will be returned.
- In path-based database, if the specified state layer is not available, then the
state reader won't be created and an error will be returned.
This change also contains a stricter semantics regarding the `Commit` operation: once it has been performed, the trie is no longer usable, and certain operations will return an error.
