refactor: Consistent use of walletName vs walletFileName

[theborakompanioni]

It is not totally clear, when a wallet name is needed, if the filename (including extension .jmdat) or the "display name" (without extension) is needed. Hence, everytime the wallet name is rendered, it is first given to util function displayWalletName. This can be made more obvious and the wallet filename, as well as the wallet "display name" should be made statically available in the WalletContext.

Hint: There is already a type Api.WalletName which actually means the "wallet filename". Change/introduce types to make this more obvious.

[theborakompanioni]

Blocked by #621

[theborakompanioni]

Idea: When this is consistently done, Jam could store meta information in the filename, e.g. wallet birthday (jam_<wallet_name>_20090103.jmdat). This might be one way for Jam to store some info about the wallet permanently.

[kristapsk]

Idea: When this is consistently done, Jam could store meta information in the filename, e.g. wallet birthday (jam_<wallet_name>_20090103.jmdat). This might be one way for Jam to store some info about the wallet permanently.

Various metadata could be stored in wallet .jmdat file itself by JM code.

[theborakompanioni]

Idea: When this is consistently done, Jam could store meta information in the filename, e.g. wallet birthday (jam_<wallet_name>_20090103.jmdat). This might be one way for Jam to store some info about the wallet permanently.

Various metadata could be stored in wallet .jmdat file itself by JM code.

Thanks @kristapsk!
It was a very stupid thought of mine. 😬

Let's focus on more important things first!
(e.g. access to blocks (blockheight) would be a nice-to-have for Jam - will open a ticket).