chore(tree): log error on unreachable

[shekhirin]

Unreachable panic turned out to be not that unreachable on full node, so we better log the details of this error.

[codecov]

Codecov Report

Merging #4185 (a5c1a03) into main (7223649) will decrease coverage by 0.06%.
Report is 2 commits behind head on main.
The diff coverage is 0.00%.

Files Changed	Coverage Δ
crates/blockchain-tree/src/blockchain_tree.rs	82.74% <0.00%> (-0.64%)	⬇️

... and 8 files with indirect coverage changes

Flag	Coverage Δ
integration-tests	16.89% <0.00%> (-0.03%)	⬇️
unit-tests	64.20% <0.00%> (-0.05%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
reth binary	26.60% <ø> (-0.34%)	⬇️
blockchain tree	82.56% <0.00%> (-0.27%)	⬇️
pipeline	90.07% <ø> (ø)
storage (db)	74.75% <ø> (ø)
trie	94.67% <ø> (-0.05%)	⬇️
txpool	52.00% <ø> (+0.57%)	⬆️
networking	77.72% <ø> (-0.06%)	⬇️
rpc	58.66% <ø> (-0.03%)	⬇️
consensus	63.73% <ø> (ø)
revm	32.19% <ø> (ø)
payload builder	6.57% <ø> (ø)
primitives	87.82% <ø> (-0.02%)	⬇️