Update development instructions and guidelines (#29)

* Delete outdated development instructions for Next.js + Tailwind and Python; add comprehensive guidelines for PostgreSQL DBA, Angular, ASP.NET REST APIs, Azure Functions with TypeScript, Bicep, Blazor, CMake with vcpkg, C#, .NET MAUI, GenAIScript, Terraform for Azure, localization, and markdown standards.

* Update documentation and prompts for consistency and clarity

- Standardized description formatting in various markdown files to use single quotes.
- Added error handling utility in update-readme.js for safer file operations.
- Improved title extraction logic in update-readme.js to handle frontmatter more robustly.
- Updated chat modes section in README to reflect new emoji and sorted chat mode links.
- Cleaned up various instruction files for better readability and consistency.
- Ensured all markdown files end with a newline for better compatibility with version control.

* Remove standardize-frontmatter.js script

* Add usage instructions for creating and switching chat modes in README.md

* Update README.md generation script to enhance instructions and usage details for custom chat modes

* Update README.md and update-readme.js for improved instruction clarity and consistency

* Refactor README.md links and update readme script for improved clarity and consistency in instructions

* Update README.md and update-readme.js for improved instruction clarity and consistency

* Changing from a patch to regen approach for the readme

* Bit more cleanup for how to show things in the readme

* Adding missing description

* Another missing description

---------

Co-authored-by: Aaron Powell <me@aaron-powell.com>

prompts/csharp-mstest.prompt.md

@@ -1,7 +1,7 @@
 ---
-mode: "agent"
-tools: ["changes", "codebase", "editFiles", "problems", "search"]
-description: "Get best practices for MSTest unit testing, including data-driven tests"
+mode: 'agent'
+tools: ['changes', 'codebase', 'editFiles', 'problems', 'search']
+description: 'Get best practices for MSTest unit testing, including data-driven tests'
 ---
 
 # MSTest Best Practices
@@ -65,4 +65,4 @@ Your goal is to help me write effective unit tests with MSTest, covering both st
 * Group tests by feature or component
 * Use test categories with `[TestCategory("Category")]`
 * Use test priorities with `[Priority(1)]` for critical tests
-* Use `[Owner("DeveloperName")]` to indicate ownership
+* Use `[Owner("DeveloperName")]` to indicate ownership