add send-to-self transaction and value transfers kinds

[Oscar-Pepper]

this solves a concern from @juanky201271 that some transactions do not create any value transfers and therefore some information is missing from the UI and also the user has no information about the status of a transaction the migrates funds etc.

• adds a new transaction and value transfer kind send-to-self so all transaction create at least 1 value transfer
• renames note-to-self to memo-to-self as there was confusion
• defines a send-to-self transaction as a sending transaction that does not send to another capability, and is not a shield
• defines a send-to-self value transfer as a transfer that is created for a send-to-self transaction when there is no memos in the received notes
• fixes a bug with shield value transfer where is did not check shielded notes were received, meaning t -> t would be listed as a shield

[fluidvanadium]

i heard this is urgent. it can merge now. i will try to update this comments