[feature] Move + alias account via settings panel

[tsmethurst]

Description

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This pull request adds a migration section to the user settings panel, allowing users to set and unset aliases, and to initiate a Move activity, using the API endpoints added in #2518.

Along the way, it also does a bit more typescript conversion and tidying up, and adds a new input type for HookedForms: the Array input type. This is similar to the FieldArray input type, but presents just the values when parsed, not key/value pairings.

The documentation endpoints linked to in the new settings panel section are not yet written. I'll write up a bunch of documentation for this whole Move and Alias thing in a separate PR.

relates to #130

Checklist

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• I/we have read the GoToSocial contribution guidelines.
• I/we have discussed the proposed changes already, either in an issue on the repository, or in the Matrix chat.
• I/we have performed a self-review of added code.
• I/we have written code that is legible and maintainable by others.
• I/we have commented the added code, particularly in hard-to-understand areas.
• I/we have made any necessary changes to documentation.
• I/we have added tests that cover new code.
• I/we have run tests and they pass locally with the changes.
• I/we have run go fmt ./... and golangci-lint run.