Enable extension API to open to specific SARIF result

[chrishuynhc]

Currently, there is not an exposed extension API that will allow other extensions to open the SARIF viewer to a specific result. This feature would allow our extension to generate static analysis results and open the user directly to issues based on a specified result id.

[50Wliu]

Proposal: Expose a new API, async selectResult(uri: Uri, runIndex: number, resultIndex: number): void.

Rationale: There is already an internal method, panel.select, that takes in a Result and opens the editor/line number corresponding to that Result. A unique Result can be looked up through the three parameters above. Hence, there should be a minimal amount of work required in the extension to enable this scenario. All in all, the full implementation of the API could look something like this:

function selectResult(uri: Uri, runIndex: number, resultIndex: number): void {
    const log = store.logs.find(log => log._uri === uri.toString());
    const result = log?.runs[runIndex]?.results?.[resultIndex];
    if (!result) return;

    panel.select(result);
}