fix: updated core dependency to 0.4.0

[alyldas]

Summary

• Update the @textfilters/core dependency range to ^0.4.0.
• Regenerate the package lock against the published core 0.4.0 package.
• Preserve package runtime behavior and public APIs while adopting the current shared contract release.

Validation

• npm ci with a temporary npm cache
• npm run check
• npm run benchmark:email
• npm pack --dry-run
• npm ls @textfilters/core --depth=0

Benchmark Evidence

Baseline origin/main:

• check direct email: 0.0044 avg ms
• censor late-match email: 0.2088 avg ms

This branch:

• check direct email: 0.0035 avg ms
• censor late-match email: 0.2055 avg ms

The additive core 0.4.0 aliases do not change package runtime behavior, and no benchmark regression was observed.

Compatibility Notes

• Public APIs are unchanged.
• Existing filter factories, aliases, exports, and scanner contract names remain compatible.
• The core dependency floor moves to ^0.4.0; release workflows, permissions, and required secrets are unchanged.

Closes #38

No publish, no merge, no tag/release.