* cmd/geth, ethdb/pebble: polish method naming and code comment
* implement db stat for pebble
* cmd, core, ethdb, internal, trie: remove db property selector
* cmd, core, ethdb: fix function description
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Co-authored-by: prpeh <prpeh@proton.me>
Co-authored-by: Gary Rong <garyrong0905@gmail.com>