Add Lingo.dev i18n Agent for GitHub Copilot (#432)

* Add Lingo.dev i18n Agent to GitHub Copilot customizations

This commit adds the Lingo.dev internationalization agent to the awesome-copilot collection. The agent provides systematic, checklist-driven i18n implementation for web applications.

Features:
- Expert at implementing internationalization (i18n) in web applications
- Systematic, checklist-driven approach using the i18n_checklist tool
- MCP server integration via SSE (https://mcp.lingo.dev/main)
- Supports comprehensive multi-language setup

The agent is added in alphabetical order to docs/README.agents.md and includes:
- Agent definition file: agents/lingodotdev-i18n.agent.md
- Installation badges for VS Code, VS Code Insiders, and Visual Studio
- MCP server configuration for the Lingo.dev service

More information: https://lingo.dev/mcp/github-copilot-agents

* Fix Lingo.dev branding in agent name

- Changed agent name from 'i18n-setup' to 'Lingo.dev i18n Agent'
- This ensures proper branding is displayed in the README
- Re-ran eng/update-readme.mjs to regenerate documentation

* Update agent name to 'Lingo.dev Localization (i18n) Agent'

- Changed from 'Lingo.dev i18n Agent' to include 'Localization'
- More user-friendly while keeping technical term in parentheses
- Follows pattern of other agents like 'Azure Data Explorer (Kusto)'
- Makes it discoverable for both localization and i18n searches

Author: maxprilutskiy

agents/lingodotdev-i18n.agent.md

@@ -0,0 +1,39 @@
+---
+name: Lingo.dev Localization (i18n) Agent
+description: Expert at implementing internationalization (i18n) in web applications using a systematic, checklist-driven approach.
+tools:
+  - shell
+  - read
+  - edit
+  - search
+  - lingo/*
+mcp-servers:
+  lingo:
+    type: "sse"
+    url: "https://mcp.lingo.dev/main"
+    tools: ["*"]
+---
+
+You are an i18n implementation specialist. You help developers set up comprehensive multi-language support in their web applications.
+
+## Your Workflow
+
+**CRITICAL: ALWAYS start by calling the `i18n_checklist` tool with `step_number: 1` and `done: false`.**
+
+This tool will tell you exactly what to do. Follow its instructions precisely:
+
+1. Call the tool with `done: false` to see what's required for the current step
+2. Complete the requirements
+3. Call the tool with `done: true` and provide evidence
+4. The tool will give you the next step - repeat until all steps are complete
+
+**NEVER skip steps. NEVER implement before checking the tool. ALWAYS follow the checklist.**
+
+The checklist tool controls the entire workflow and will guide you through:
+
+- Analyzing the project
+- Fetching relevant documentation
+- Implementing each piece of i18n step-by-step
+- Validating your work with builds
+
+Trust the tool - it knows what needs to happen and when.

docs/README.agents.md

@@ -72,6 +72,7 @@ Custom agents for GitHub Copilot, making it easy for users and organizations to
 | [Kusto Assistant: Azure Data Explorer (Kusto) Engineering Assistant](../agents/kusto-assistant.agent.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Fkusto-assistant.agent.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode-insiders%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Fkusto-assistant.agent.md) | Expert KQL assistant for live Azure Data Explorer analysis via Azure MCP server |  |
 | [Laravel Expert Agent](../agents/laravel-expert-agent.agent.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Flaravel-expert-agent.agent.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode-insiders%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Flaravel-expert-agent.agent.md) | Expert Laravel development assistant specializing in modern Laravel 12+ applications with Eloquent, Artisan, testing, and best practices |  |
 | [Launchdarkly Flag Cleanup](../agents/launchdarkly-flag-cleanup.agent.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Flaunchdarkly-flag-cleanup.agent.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode-insiders%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Flaunchdarkly-flag-cleanup.agent.md) | A specialized GitHub Copilot agent that uses the LaunchDarkly MCP server to safely automate feature flag cleanup workflows. This agent determines removal readiness, identifies the correct forward value, and creates PRs that preserve production behavior while removing obsolete flags and updating stale defaults. | [launchdarkly](https://github.com/mcp/launchdarkly/mcp-server)<br />[![Install MCP](https://img.shields.io/badge/Install-VS_Code-0098FF?style=flat-square)](https://aka.ms/awesome-copilot/install/mcp-vscode?name=launchdarkly&config=%7B%22command%22%3A%22npx%22%2C%22args%22%3A%5B%22-y%22%2C%22--package%22%2C%22%2540launchdarkly%252Fmcp-server%22%2C%22--%22%2C%22mcp%22%2C%22start%22%2C%22--api-key%22%2C%22%2524LD_ACCESS_TOKEN%22%5D%2C%22env%22%3A%7B%7D%7D)<br />[![Install MCP](https://img.shields.io/badge/Install-VS_Code_Insiders-24bfa5?style=flat-square)](https://aka.ms/awesome-copilot/install/mcp-vscodeinsiders?name=launchdarkly&config=%7B%22command%22%3A%22npx%22%2C%22args%22%3A%5B%22-y%22%2C%22--package%22%2C%22%2540launchdarkly%252Fmcp-server%22%2C%22--%22%2C%22mcp%22%2C%22start%22%2C%22--api-key%22%2C%22%2524LD_ACCESS_TOKEN%22%5D%2C%22env%22%3A%7B%7D%7D)<br />[![Install MCP](https://img.shields.io/badge/Install-Visual_Studio-C16FDE?style=flat-square)](https://aka.ms/awesome-copilot/install/mcp-visualstudio/mcp-install?%7B%22command%22%3A%22npx%22%2C%22args%22%3A%5B%22-y%22%2C%22--package%22%2C%22%2540launchdarkly%252Fmcp-server%22%2C%22--%22%2C%22mcp%22%2C%22start%22%2C%22--api-key%22%2C%22%2524LD_ACCESS_TOKEN%22%5D%2C%22env%22%3A%7B%7D%7D) |
+| [Lingo.dev Localization (i18n) Agent](../agents/lingodotdev-i18n.agent.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Flingodotdev-i18n.agent.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode-insiders%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Flingodotdev-i18n.agent.md) | Expert at implementing internationalization (i18n) in web applications using a systematic, checklist-driven approach. | lingo<br />[![Install MCP](https://img.shields.io/badge/Install-VS_Code-0098FF?style=flat-square)](https://aka.ms/awesome-copilot/install/mcp-vscode?name=lingo&config=%7B%22command%22%3A%22%22%2C%22args%22%3A%5B%5D%2C%22env%22%3A%7B%7D%7D)<br />[![Install MCP](https://img.shields.io/badge/Install-VS_Code_Insiders-24bfa5?style=flat-square)](https://aka.ms/awesome-copilot/install/mcp-vscodeinsiders?name=lingo&config=%7B%22command%22%3A%22%22%2C%22args%22%3A%5B%5D%2C%22env%22%3A%7B%7D%7D)<br />[![Install MCP](https://img.shields.io/badge/Install-Visual_Studio-C16FDE?style=flat-square)](https://aka.ms/awesome-copilot/install/mcp-visualstudio/mcp-install?%7B%22command%22%3A%22%22%2C%22args%22%3A%5B%5D%2C%22env%22%3A%7B%7D%7D) |
 | [Mentor mode instructions](../agents/mentor.agent.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Fmentor.agent.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode-insiders%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Fmentor.agent.md) | Help mentor the engineer by providing guidance and support. |  |
 | [Meta Agentic Project Scaffold](../agents/meta-agentic-project-scaffold.agent.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Fmeta-agentic-project-scaffold.agent.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode-insiders%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Fmeta-agentic-project-scaffold.agent.md) | Meta agentic project creation assistant to help users create and manage project workflows effectively. |  |
 | [Microsoft Agent Framework .NET mode instructions](../agents/microsoft-agent-framework-dotnet.agent.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Fmicrosoft-agent-framework-dotnet.agent.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/agent?url=vscode-insiders%3Achat-agent%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fagents%2Fmicrosoft-agent-framework-dotnet.agent.md) | Create, update, refactor, explain or work with code using the .NET version of Microsoft Agent Framework. |  |