vscode extension - implement external terminal and add problems

[P-de-Jong]

External terminals Enable connecting to external terminals via port number input, allowing users to work with terminals outside VS Code. This allows sending context to prompts in external terminals. I work with 2 instances of vscode open, frontend and backend. This allows me to have a single terminal open with Opencode.

Start opencode in a terminal specifying a port
Run command "Opencode - Register External Terminal"
Enter port

Problems I find myself copy/pasting the content of the problems window to Opencode a lot. This adds a command which sends the content to Opencode.