* Redefine `seq[Blob]` => `seq[SnapProof]` for `snap/1` protocol
why:
Proof nodes are traded as `Blob` type items rather than Nim objects. So
the RLP transcoder must not extra wrap proofs which are of type
seq[Blob]. Without custom encoding one would produce a
`list(blob(item1), blob(item2) ..)` instead of `list(item1, item2 ..)`.
* Limit leaf extractor by RLP size rather than number of items
why:
To be used serving `snap/1` requests, the result of function
`hexaryRangeLeafsProof()` is limited by the maximal space
needed to serialise the result which will be part of the
`snap/1` repsonse.
* Let the range extractor `hexaryRangeLeafsProof()` return RLP list sizes
why:
When collecting accounts, the size oft the accounts list when encoded
as RLP is continually updated. So the summed up value is available
anyway. For the proof nodes list, there are not many (~ 10) so summing
up is not expensive here.
* Re-model persistent database access
why:
Storage slots healing just run on the wrong sub-trie (i.e. the wrong
key mapping). So get/put and bulk functions now use the definitions
in `snapdb_desc` (earlier there were some shortcuts for `get()`.)
* Fixes: missing return code, typo, redundant imports etc.
* Remove obsolete debugging directives from `worker_desc` module
* Correct failing unit tests for storage slots trie inspection
why:
Some pathological cases for the extended tests do not produce any
hexary trie data. This is rightly detected by the trie inspection
and the result checks needed to adjusted.
* For snap sync, publish `EthWireRef` in sync descriptor
why:
currently used for noise control
* Detect and reuse existing storage slots
* Provide healing module for storage slots
* Update statistic ticker (adding range factor for unprocessed storage)
* Complete mere function for work item ranges
why:
Merging interval into existing partial item was missing
* Show av storage queue lengths in ticker
detail;
Previous attempt shows average completeness which did not tell much
* Correct the meaning of the storage counter (per pivot)
detail:
Is the # accounts that have a storage saved