Add management for Recent Connections with profiling and deletion

[brandochn]

This pull request implements new features for managing recent connections in the Light Query Profiler extension, most notably adding the ability to delete individual recent connections both in the backend and the VS Code UI. It also introduces a "Start Profiling" button for recent connections, enabling users to quickly begin profiling with a single click. Supporting changes include backend API additions, TypeScript client methods, UI wiring, and comprehensive tests. Minor refactoring for code style consistency (single quotes) is also included.

Recent Connections Management:

• Added a new DeleteRecentConnectionAsync JSON-RPC endpoint to the .NET backend, allowing deletion of recent connections by their unique identifier. Includes a request model and robust error handling. [1] [2]
• Implemented corresponding unit tests for the new backend endpoint to ensure correct behavior and error propagation.
• Exposed a new deleteRecentConnection(id) method on the TypeScript ProfilerClient for frontend consumers to trigger deletions. [1] [2]
• Updated the changelog and extension manifest to reflect the new features and bump the version to 1.4.0. [1] [2]

UI/UX Improvements:

• Wired up the Recent Connections panel to include both a "Start Profiling" (▶ Start) button for one-click profiling and a "Delete" (✕ Delete) button to remove entries, refreshing the list in place. Also added a new public method startProfilingWithConnection(connection) on ProfilerPanelProvider for programmatic connection and start. [1] [2]

Code Quality and Consistency:

• Refactored the VS Code extension codebase to use single quotes for string literals, improving style consistency. [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14]