controller::extract_chain_id_from_db() does not properly handle dirty db

[heifner]

Seems like we would want to allow any exception to propagate up. And only return an empty optional if db.revision() < 1.

Most importantly this currently causes confusing if the database is dirty because of an unclean shutdown.

Apr 21 02:06:22 eos nodeos[17876]: warn  2022-04-21T02:06:22.015 nodeos    chain_plugin.cpp:1321         plugin_initialize    ] 3110006 plugin_config_exception: Incorrect plugin configuration
Apr 21 02:06:22 eos nodeos[17876]: Genesis state is necessary to initialize fresh blockchain state but genesis state could not be found in the blocks log. Please either load from snapshot or find a blocks log that starts from genesis.
Apr 21 02:06:22 eos nodeos[17876]:     {}
Apr 21 02:06:22 eos nodeos[17876]:     nodeos  chain_plugin.cpp:1154 plugin_initialize
Apr 21 02:06:22 eos nodeos[17876]: error 2022-04-21T02:06:22.015 nodeos    main.cpp:163                  main                 ] 3110006 plugin_config_exception: Incorrect plugin configuration
Apr 21 02:06:22 eos nodeos[17876]: Genesis state is necessary to initialize fresh blockchain state but genesis state could not be found in the blocks log. Please either load from snapshot or find a blocks log that starts from genesis.
Apr 21 02:06:22 eos nodeos[17876]:     {}
Apr 21 02:06:22 eos nodeos[17876]:     nodeos  chain_plugin.cpp:1154 plugin_initialize
Apr 21 02:06:22 eos nodeos[17876]: rethrow
Apr 21 02:06:22 eos nodeos[17876]:     {}
Apr 21 02:06:22 eos nodeos[17876]:     nodeos  chain_plugin.cpp:1321 plugin_initialize

Should use find instead of get and return empty optional if not found.

[spoonincode]

I kind of wonder if something like the chainid should be stored in chainbase's header so it's possible to interrogate it even when dirty. Or more generally speaking, any write-once sort of data could be stored. Not sure I'm coming up with good uses though 🤔

[vladtr]

@heifner we should probably still swallow "db_error_code::not_found" so if there is no db it will be created. Edit: probably all except std::system_error exceptions should be propagated