Fix C lint errors

## C Linting Failures

Linting failures were detected in the automated lint workflow run.

### Workflow Details

- Run: https://github.com/stdlib-js/stdlib/actions/runs/29215027911
- Type: C Linting
- Date: 2026-07-13 00:35:50 UTC

### Error Details

```
lib/node_modules/@stdlib/ndarray/base/every/src/dispatch.c:221:11: style: Variable 's1' can be declared as pointer to const [constVariablePointer]
int64_t *s1;
^
```

### Pull Request Instructions

- Please use the following PR title format:
"chore: fix C lint errors (issue #)".
- Reference this issue in the "Related Issues" section of the PR body as "resolves #".

Open lib/node_modules/@stdlib/ndarray/base/every/src/dispatch.c at line 221 and inspect the lint diagnostic for s1. Update the declaration to satisfy constVariablePointer, then rerun the C lint workflow or equivalent lint check and confirm the reported failure is gone.

Written by the indexing model from the issue text.