Needs more RPGLE support e.g., prompting `dcl-pr`

[jwoehr]

I assume this is the issue tracker for vscode-rpgle also since that repo does not have its own issue tracker

Is your feature request related to a problem? Please describe. Some RPGLE specification are not supported in the vscode-rpgle extension, e.g., dcl-pr

Describe the solution you'd like Extend vscode-rpgle

Describe alternatives you've considered Snippet suggested by @p-behr

"Prototype - Program": {
		"prefix": "dcl-pr",
		"body": [
		"dcl-pr $1 extpgm('$2');",
		"\t$3;",
		"end-pr;",
		"$4"
		],
		"description": "Create prototype for external program"
		}

Additional context