fix: split test:lint and test:lint:staged scripts

[willfarrell]

Summary

• test:lint was incorrectly running biome check --staged — it should lint the entire codebase, not just staged files
• Added new test:lint:staged script for the staged-only variant (used by pre-commit hook)
• Updated git:lint-staged to call test:lint:staged instead of test:lint

Resulting scripts

"git:lint-staged": "npm run test:lint:staged",
"test:lint": "biome check --no-errors-on-unmatched",
"test:lint:staged": "biome check --staged --no-errors-on-unmatched",

Test plan

• Verify npm run test:lint lints all files (not just staged)
• Verify npm run test:lint:staged lints only staged files
• Verify pre-commit hook still works via git:lint-staged