fix: patch 14 npm audit vulnerabilities (#50)

Dependency updates resolve 14 of 17 npm audit vulnerabilities (8 high, 5
moderate, 1 low).

Fixed packages: `@isaacs/brace-expansion`, `ajv`, `brace-expansion`,
`diff`, `flatted`, `follow-redirects`, `lodash`, `markdown-it`,
`minimatch`, `path-to-regexp`, `picomatch`, `qs`, `underscore`,
`undici`.

Remaining 3 high (`serialize-javascript` via `mocha` →
`@vscode/test-cli`) have no upstream fix and are dev-only, not shipped
in VSIX.

Author: tembleking

flake.lock

@@ -78,7 +78,7 @@
                 vsce
                 pre-commit
                 just
-                nodePackages.typescript-language-server
+                typescript-language-server
                 prefetch-npm-deps
                 sd
               ]