chore: update VS Code plugin npm dependencies (consolidate dependabot PRs)

[Copilot]

Summary

Consolidates 6 open Dependabot security PRs (#725, #727, #728, #729, #730, #731) into a single dependency update by running npm audit fix (and npm audit fix --force for the client where a major version bump was needed).

Changes

DevSkim-VSCode-Plugin/ (root)

• picomatch bumped from 2.3.1 → 2.3.2
• undici bumped to 7.24.6
• qs bumped to 6.15.0
• minimatch bumped to latest patched versions
• Additional transitive dependency fixes

DevSkim-VSCode-Plugin/client/

• @vscode/test-electron bumped from 1.6.1 → 2.5.2 (major bump; removes vulnerable @tootallnate/once and http-proxy-agent)
• minimatch bumped to 3.1.5

Changelog.md — new entry [1.0.77] documenting all dependency updates

Dependabot PRs Resolved

PR	Package	Change
#725	qs	6.14.1 → 6.15.0
#727	minimatch (client)	3.1.2 → 3.1.5
#728	minimatch (root)	3.1.2/10.1.2 → 3.1.5/10.2.4+
#729	@vscode/test-electron + @tootallnate/once	1.6.1 → 2.5.2
#730	undici	7.20.0 → 7.24.6
#731	picomatch	2.3.1 → 2.3.2

Both npm audit runs now report 0 vulnerabilities.