Resolve outstanding `mage check:go` linter findings

### Summary

Resolve the outstanding `golangci-lint` findings reported by `mage check:go` on `main`.

Current findings:

```shell
407 issues:
* errcheck: 18
* gocheckcompilerdirectives: 1
* goconst: 351
* gosec: 12
* misspell: 1
* noctx: 5
* nolintlint: 4
* prealloc: 5
* staticcheck: 10
```

### Criteria for completion

- [ ] All current reported findings are addressed.
- [ ] `mage check:go` exits 0 on `main` (no findings, no panics).
- [ ] No new `//nolint:` annotations introduced unless accompanied by an explanatory comment per the `nolintlint` rule.

Start by running `mage check:go` on `main` and use its output to locate the 407 reported findings across the Go codebase. Address each listed linter category, then rerun the command until it exits 0 without panics or findings. Any new `//nolint:` annotation must include an explanatory comment.

Written by the indexing model from the issue text.