Fix security vulnerabilities (#767)

* fix: resolve npm audit vulnerabilities, refresh license cache, rebuild dist

- npm audit fix resolves brace-expansion (high), fast-xml-parser (high),
  and undici (moderate) advisories via transitive dependency updates
- Regenerated .licenses/npm cache to match updated dependency tree
- Rebuilt dist/setup and dist/cache-save bundles

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* fix: sync vendored install-dotnet.ps1 with upstream dot.net script

Basic Validation was failing because the vendored copy of
externals/install-dotnet.ps1 was out of date compared to the live
script served from https://dot.net/v1/dotnet-install.ps1, which
installation-scripts.test.ts compares against on every run.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

.licenses/npm/path-expression-matcher.dep.yml

@@ -1,6 +1,6 @@
 ---
 name: path-expression-matcher
-version: 1.5.0
+version: 1.6.2
 type: npm
 summary: Efficient path tracking and pattern matching for XML/JSON parsers
 homepage: https://github.com/NaturalIntelligence/path-expression-matcher#readme