Add lsp-setup skill for configuring LSP servers in Copilot CLI

Adds a new skill that helps users install and configure Language Server
Protocol servers for GitHub Copilot CLI. Includes:

- Interactive workflow: detect OS, install server, write config, verify
- Bundled reference with 14 languages (Java/jdtls, TypeScript, Python,
  Go, Rust, C/C++, C#, Ruby, PHP, Kotlin, Swift, Lua, YAML, Bash)
- Per-OS install commands and ready-to-use lsp-config.json snippets
- Support for both user-level and repo-level configuration

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

docs/README.skills.md

@@ -178,6 +178,7 @@ See [CONTRIBUTING.md](../CONTRIBUTING.md#adding-skills) for guidelines on how to
 | [kotlin-mcp-server-generator](../skills/kotlin-mcp-server-generator/SKILL.md) | Generate a complete Kotlin MCP server project with proper structure, dependencies, and implementation using the official io.modelcontextprotocol:kotlin-sdk library. | None |
 | [kotlin-springboot](../skills/kotlin-springboot/SKILL.md) | Get best practices for developing applications with Spring Boot and Kotlin. | None |
 | [legacy-circuit-mockups](../skills/legacy-circuit-mockups/SKILL.md) | Generate breadboard circuit mockups and visual diagrams using HTML5 Canvas drawing techniques. Use when asked to create circuit layouts, visualize electronic component placements, draw breadboard diagrams, mockup 6502 builds, generate retro computer schematics, or design vintage electronics projects. Supports 555 timers, W65C02S microprocessors, 28C256 EEPROMs, W65C22 VIA chips, 7400-series logic gates, LEDs, resistors, capacitors, switches, buttons, crystals, and wires. | `references/28256-eeprom.md`<br />`references/555.md`<br />`references/6502.md`<br />`references/6522.md`<br />`references/6C62256.md`<br />`references/7400-series.md`<br />`references/assembly-compiler.md`<br />`references/assembly-language.md`<br />`references/basic-electronic-components.md`<br />`references/breadboard.md`<br />`references/common-breadboard-components.md`<br />`references/connecting-electronic-components.md`<br />`references/emulator-28256-eeprom.md`<br />`references/emulator-6502.md`<br />`references/emulator-6522.md`<br />`references/emulator-6C62256.md`<br />`references/emulator-lcd.md`<br />`references/lcd.md`<br />`references/minipro.md`<br />`references/t48eeprom-programmer.md` |
+| [lsp-setup](../skills/lsp-setup/SKILL.md) | Install and configure LSP servers for any programming language to work with GitHub Copilot CLI. Detects the OS, installs the right LSP server, and writes the lsp-config.json configuration. Say "setup LSP" to start. | `references/lsp-servers.md` |
 | [make-repo-contribution](../skills/make-repo-contribution/SKILL.md) | All changes to code must follow the guidance documented in the repository. Before any issue is filed, branch is made, commits generated, or pull request (or PR) created, a search must be done to ensure the right steps are followed. Whenever asked to create an issue, commit messages, to push code, or create a PR, use this skill so everything is done correctly. | `assets/issue-template.md`<br />`assets/pr-template.md` |
 | [make-skill-template](../skills/make-skill-template/SKILL.md) | Create new Agent Skills for GitHub Copilot from prompts or by duplicating this template. Use when asked to "create a skill", "make a new skill", "scaffold a skill", or when building specialized AI capabilities with bundled resources. Generates SKILL.md files with proper frontmatter, directory structure, and optional scripts/references/assets folders. | None |
 | [markdown-to-html](../skills/markdown-to-html/SKILL.md) | Convert Markdown files to HTML similar to `marked.js`, `pandoc`, `gomarkdown/markdown`, or similar tools; or writing custom script to convert markdown to html and/or working on web template systems like `jekyll/jekyll`, `gohugoio/hugo`, or similar web templating systems that utilize markdown documents, converting them to html. Use when asked to "convert markdown to html", "transform md to html", "render markdown", "generate html from markdown", or when working with .md files and/or web a templating system that converts markdown to HTML output. Supports CLI and Node.js workflows with GFM, CommonMark, and standard Markdown flavors. | `references/basic-markdown-to-html.md`<br />`references/basic-markdown.md`<br />`references/code-blocks-to-html.md`<br />`references/code-blocks.md`<br />`references/collapsed-sections-to-html.md`<br />`references/collapsed-sections.md`<br />`references/gomarkdown.md`<br />`references/hugo.md`<br />`references/jekyll.md`<br />`references/marked.md`<br />`references/pandoc.md`<br />`references/tables-to-html.md`<br />`references/tables.md`<br />`references/writing-mathematical-expressions-to-html.md`<br />`references/writing-mathematical-expressions.md` |