Enable as many linters as possible in golangci-lint and resolve linter errors

[whatsacomputertho]

Overview

Currently we use the default configuration for golangci-lint. To improve our code quality, we should consider enabling more than just the default set of linters and resolving their errors. For reference, see:

• https://golangci-lint.run/usage/linters/

Acceptance

• In .golangci-lint.yaml, we set default: all
• In our source code, we work through the resulting linter errors
• In .golangci-lint.yaml, we selectively disable linters we deem non-applicable (Note: When in doubt we should leave the linter enabled)
• All of the enabled linters pass without error