fix(workbench): Reset project state when a window switches projects

Opening another project in the same window left the previous project's state in
module-level stores: Amend and the commit message carried over, debug sessions kept
running, and Git Log, usages, hierarchy, inspection, HTTP client, recent locations,
navigation history and notifications still showed the old project.

Reset each of them on a project root change, stop the old debug sessions, ask about
unsaved changes before leaving a project, close the settings window (it would apply
to the new project) and end the indexing task when a scan is cancelled.

src/features/github/index.ts

@@ -9,7 +9,7 @@ import { registerOverlay, registerToolWindow } from "@/workbench/contributions";
 import { GithubDialogHost } from "./dialogs";
 import { checkoutAction, createPullRequest, openInBrowser, showPullRequests, WINDOW } from "./ops";
 import { PullRequestsHeader, PullRequestsView } from "./PullRequestsView";
-import { DEFAULT_QUERY, refreshAll, useGithub } from "./store";
+import { refreshAll, resetGithub } from "./store";
 
 const WHEN = "projectOpen";
 
@@ -65,10 +65,8 @@ export function activate(): () => void {
       },
       { id: "github.refresh", title: "Refresh Pull Requests", category: "GitHub", icon: "refresh", when: WHEN, run: () => refreshAll() },
     ]),
-    // Another project: start over.
     useProject.subscribe((s, prev) => {
-      if (s.project?.root === prev.project?.root) return;
-      useGithub.setState({ availability: null, list: [], selected: null, details: null, reviewComments: [], query: DEFAULT_QUERY });
+      if (s.project?.root !== prev.project?.root) resetGithub();
     }),
   ];
   return () => disposers.reverse().forEach((d) => d());

src/features/github/store.ts

@@ -163,6 +163,12 @@ export function cancelBusy() {
 
 const diffCache = new Map<string, PrDiffRevisions>();
 
+/** Another project: start over. */
+export function resetGithub() {
+  diffCache.clear();
+  useGithub.setState({ availability: null, list: [], selected: null, details: null, reviewComments: [], query: DEFAULT_QUERY });
+}
+
 /** Fetches what the local repository lacks to diff `pr`, once per head commit. */
 export async function diffRevisions(pr: PullRequestDetails): Promise<PrDiffRevisions | null> {
   const key = `${pr.summary.number}:${pr.headOid}:${pr.baseOid}`;