chore: update in-range dev dependencies

Updates all devDependencies to their latest compatible versions within
the semver ranges already declared in package.json:
- @github/copilot 1.0.10 -> 1.0.36
- @types/node 25.5.0 -> 25.6.0
- @types/vscode 1.110.0 -> 1.116.0 (6 new VS Code API version types)
- @typescript-eslint/eslint-plugin 8.57.1 -> 8.59.0
- @typescript-eslint/parser 8.57.1 -> 8.59.0
- @vscode/vsce 3.7.1 -> 3.9.1
- esbuild 0.27.4 -> 0.28.0
- eslint 10.1.0 -> 10.2.1
- jsdom 29.0.1 -> 29.1.0
- stylelint 17.5.0 -> 17.9.0

TypeScript 6.0 intentionally excluded (out-of-range major upgrade).
Build verified: npm run compile passes, no errors.

Author: rajbos