[chore] Harden up boolptr logic on Accounts, warn if not set

[tsmethurst]

Description

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This pull request adds nil ptr checks in the account to api account typeutil conversion functions, which should unclog #2527 and #2514.

Unfortunately, I couldn't find the issue that was causing those ptrs to be nil in the first place, or even replicate the bug on the testrig. Some warning logs have been added to the nil ptr checks so we can hopefully gather some info on when this happens, while working around the bug.

Also adds a bunch of tests for a typical Honk account, in an attempt to reproduce the bug. The reproduction failed, but the tests are still good to have.

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.