Edit workspace files directly on web (#2270)

* feat(files): edit workspace files on web

Keep source buffers synchronized with host file changes and require an explicit overwrite or reload when revisions diverge.

* feat(panels): surface and protect modified tabs

Expose tooltip and modification state through the generic panel boundary so tabs can show stable metadata and guard every close route consistently.

* fix(tests): use portable fake timeout handle

* fix(files): harden editor conflict handling

Preserve modified panel state across tab eviction, use precise revisions for optimistic writes, coalesce concurrent file watchers, and localize the editor interface.

* fix(files): close editor concurrency gaps

Coalesce clean reloads, preserve subscriber identities and file permissions, suspend pending saves during close confirmation, and carry precise revisions through file reads.

* test(files): expect read revision metadata

packages/app/src/screens/workspace/workspace-screen.tsx

@@ -168,6 +168,10 @@ import {
   closeBulkWorkspaceTabs,
 } from "@/screens/workspace/workspace-bulk-close";
 import { resolveCloseAgentTabPolicy } from "@/subagents";
+import {
+  getPanelInstanceAttributes,
+  useModifiedPanelTabIds,
+} from "@/panels/panel-instance-attributes";
 import { findAdjacentPane } from "@/utils/split-navigation";
 import { useIsCompactFormFactor, supportsDesktopPaneSplits } from "@/constants/layout";
 import { getIsElectron, isNative, isWeb } from "@/constants/platform";
@@ -2661,11 +2665,8 @@ function WorkspaceScreenContent({
     [archiveAgent, closeTab, closeWorkspaceTabWithCleanup, normalizedServerId, persistenceKey, t],
   );
 
-  const handleCloseDraftOrFileTab = useCallback(
-    function handleCloseDraftOrFileTab(input: {
-      tabId: string;
-      target?: WorkspaceTabTarget | null;
-    }) {
+  const handleClosePassiveTab = useCallback(
+    function handleClosePassiveTab(input: { tabId: string; target?: WorkspaceTabTarget | null }) {
       setHoveredCloseTabKey((current) => (current === input.tabId ? null : current));
       if (persistenceKey) {
         closeWorkspaceTabWithCleanup({ tabId: input.tabId, target: input.target });
@@ -2674,12 +2675,37 @@ function WorkspaceScreenContent({
     [closeWorkspaceTabWithCleanup, persistenceKey],
   );
 
+  const confirmDiscardModifiedTab = useCallback(
+    async (tabId: string): Promise<boolean> => {
+      const attributes = getPanelInstanceAttributes({
+        serverId: normalizedServerId,
+        workspaceId: normalizedWorkspaceId,
+        tabId,
+      });
+      if (!attributes.modified) return true;
+      const resumePendingSave = attributes.suspendPendingSave?.();
+      const confirmed = await confirmDialog({
+        title: t("workspace.tabs.confirmations.unsavedTitle"),
+        message: t("workspace.tabs.confirmations.unsavedMessage"),
+        confirmLabel: t("workspace.tabs.confirmations.closeWithoutSaving"),
+        cancelLabel: t("workspace.tabs.confirmations.cancel"),
+        destructive: true,
+      });
+      if (!confirmed) resumePendingSave?.();
+      return confirmed;
+    },
+    [normalizedServerId, normalizedWorkspaceId, t],
+  );
+
   const handleCloseTabById = useCallback(
     async (tabId: string) => {
       const tab = allTabDescriptorsById.get(tabId);
       if (!tab) {
         return;
       }
+      if (!(await confirmDiscardModifiedTab(tabId))) {
+        return;
+      }
       if (tab.target.kind === "terminal") {
         await handleCloseTerminalTab({ tabId, terminalId: tab.target.terminalId });
         return;
@@ -2688,9 +2714,15 @@ function WorkspaceScreenContent({
         await handleCloseAgentTab({ tabId, agentId: tab.target.agentId });
         return;
       }
-      handleCloseDraftOrFileTab({ tabId, target: tab.target });
+      handleClosePassiveTab({ tabId, target: tab.target });
     },
-    [allTabDescriptorsById, handleCloseAgentTab, handleCloseDraftOrFileTab, handleCloseTerminalTab],
+    [
+      allTabDescriptorsById,
+      confirmDiscardModifiedTab,
+      handleCloseAgentTab,
+      handleClosePassiveTab,
+      handleCloseTerminalTab,
+    ],
   );
 
   const handleCopyAgentId = useCallback(
@@ -2834,9 +2866,21 @@ function WorkspaceScreenContent({
       }
 
       const groups = classifyBulkClosableTabs(tabsToClose);
+      const modifiedCount = tabsToClose.filter(
+        (tab) =>
+          getPanelInstanceAttributes({
+            serverId: normalizedServerId,
+            workspaceId: normalizedWorkspaceId,
+            tabId: tab.tabId,
+          }).modified,
+      ).length;
+      const bulkMessage = buildBulkCloseConfirmationMessage(groups, bulkCloseConfirmationLabels);
       const confirmed = await confirmDialog({
         title,
-        message: buildBulkCloseConfirmationMessage(groups, bulkCloseConfirmationLabels),
+        message:
+          modifiedCount > 0
+            ? `${bulkMessage}\n\n${t("workspace.tabs.confirmations.bulkUnsaved", { count: modifiedCount })}`
+            : bulkMessage,
         confirmLabel: t("workspace.tabs.confirmations.close"),
         cancelLabel: t("workspace.tabs.confirmations.cancel"),
         destructive: true,
@@ -2869,6 +2913,8 @@ function WorkspaceScreenContent({
       client,
       closeTab,
       closeWorkspaceTabWithCleanup,
+      normalizedServerId,
+      normalizedWorkspaceId,
       persistenceKey,
       t,
     ],
@@ -3055,12 +3101,15 @@ function WorkspaceScreenContent({
       }
 
       if (action.id === "workspace.pane.close") {
-        for (const tabId of focusedPane.tabIds) {
-          closeWorkspaceTabWithCleanup({
-            tabId,
-            target: allTabDescriptorsById.get(tabId)?.target ?? null,
-          });
-        }
+        const tabsToClose = focusedPane.tabIds.flatMap((tabId) => {
+          const tab = allTabDescriptorsById.get(tabId);
+          return tab ? [tab] : [];
+        });
+        void handleBulkCloseTabs({
+          tabsToClose,
+          title: t("workspace.tabs.confirmations.closePaneTitle"),
+          logLabel: "from pane close",
+        });
         return true;
       }
 
@@ -3068,14 +3117,15 @@ function WorkspaceScreenContent({
     },
     [
       allTabDescriptorsById,
-      closeWorkspaceTabWithCleanup,
       focusWorkspacePane,
+      handleBulkCloseTabs,
       handleCreateDraftSplit,
       moveWorkspaceTabToPane,
       persistenceKey,
       focusedPaneTabState.activeTabId,
       focusedPaneTabState.pane,
       toggleFocusMode,
+      t,
       workspaceLayout,
     ],
   );
@@ -3210,10 +3260,16 @@ function WorkspaceScreenContent({
     [focusedPaneTabState.pane],
   );
   const focusedPaneTabIds = useMemo(() => tabs.map((tab) => tab.tabId), [tabs]);
+  const modifiedFocusedPaneTabIds = useModifiedPanelTabIds({
+    serverId: normalizedServerId,
+    workspaceId: normalizedWorkspaceId,
+    tabIds: focusedPaneTabIds,
+  });
   const focusedPaneTabDescriptorMap = useStableTabDescriptorMap(tabs);
   const { mountedTabIds: mountedFocusedPaneTabIdsSet } = useMountedTabSet({
     activeTabId,
     allTabIds: focusedPaneTabIds,
+    retainedTabIds: modifiedFocusedPaneTabIds,
     cap: 3,
   });
   const mountedFocusedPaneTabIds = useMemo(