Refactor server code to enhance logging and error handling

[OlegZee]

This pull request introduces improved logging and error handling throughout the server-side codebase, enhancing observability and robustness, especially around initialization, channel creation, OAuth configuration, and WebSocket communication. Additionally, it updates configuration files for project setup and tool integration.

Logging and Error Handling Improvements

• Replaced printfn statements with structured logging using ILogger in AppGiraffe.fs, including server initialization, channel creation, OAuth configuration, and error reporting. This provides better diagnostics and production readiness. [1] [2] [3] [4]
• Refactored the diagnostic channel creation in Diag.fs to accept a logger and log errors when channel or participant creation fails, improving traceability for channel setup issues. [1] [2] [3]
• Enhanced WebSocket message handling in SocketFlow.fs by adding detailed error logging for send/receive operations and handling specific exceptions, making debugging and client communication more reliable. [1] [2]

Configuration and Project Setup

• Added .mcp.json to configure the Playwright MCP server, enabling integration with Playwright for testing or automation.
• Updated .serena/project.yml to specify project language as bash, enable gitignore-based file ignoring, and document available/excluded tools for project automation.
• Added /cache to .serena/.gitignore to exclude cache files from version control.

Minor Code Quality Improvements

• Replaced some usages of System.Environment.CurrentDirectory and other system calls with more idiomatic F# code and fixed minor code style issues. [1] [2] [3]

These changes collectively improve the maintainability, reliability, and observability of the server application.