feat: Enable snapshots by default for all users (#313)

Change the default value of `deepnote.snapshots.enabled` from `false` to
`true` so that all users get the benefits of snapshot mode by default:
- Outputs saved to separate snapshot files
- Main .deepnote file stays cleaner with just source code
- Document stays clean until actual content changes

https://claude.ai/code/session_012kUL7YuMgYq3CR1xqnrLb5

Co-authored-by: Claude <noreply@anthropic.com>

Author: Artmann

package.json

@@ -1652,7 +1652,7 @@
                 },
                 "deepnote.snapshots.enabled": {
                     "type": "boolean",
-                    "default": false,
+                    "default": true,
                     "description": "When enabled, outputs are saved to separate snapshot files in a 'snapshots' folder instead of the main .deepnote file.",
                     "scope": "resource"
                 },

src/notebooks/deepnote/deepnoteActivationService.ts

@@ -77,7 +77,7 @@ export class DeepnoteActivationService implements IExtensionSyncActivationServic
 
         const config = workspace.getConfiguration('deepnote');
 
-        return config.get<boolean>('snapshots.enabled', false);
+        return config.get<boolean>('snapshots.enabled', true);
     }
 
     private promptReloadForSnapshots(): void {

src/notebooks/deepnote/snapshots/snapshotService.ts

@@ -328,7 +328,7 @@ export class SnapshotService implements ISnapshotMetadataService, IExtensionSync
     isSnapshotsEnabled(): boolean {
         const config = workspace.getConfiguration('deepnote');
 
-        return config.get<boolean>('snapshots.enabled', false);
+        return config.get<boolean>('snapshots.enabled', true);
     }
 
     mergeOutputsIntoBlocks(blocks: DeepnoteBlock[], outputs: Map<string, DeepnoteOutput[]>): DeepnoteBlock[] {

src/notebooks/deepnote/snapshots/snapshotService.unit.test.ts

@@ -438,7 +438,7 @@ suite('SnapshotService', () => {
     suite('isSnapshotsEnabled', () => {
         test('should return true when snapshots.enabled is true', () => {
             const mockConfig = mock<WorkspaceConfiguration>();
-            when(mockConfig.get<boolean>('snapshots.enabled', false)).thenReturn(true);
+            when(mockConfig.get<boolean>('snapshots.enabled', true)).thenReturn(true);
             when(mockedVSCodeNamespaces.workspace.getConfiguration('deepnote')).thenReturn(instance(mockConfig));
 
             const result = service.isSnapshotsEnabled();
@@ -448,7 +448,7 @@ suite('SnapshotService', () => {
 
         test('should return false when snapshots.enabled is false', () => {
             const mockConfig = mock<WorkspaceConfiguration>();
-            when(mockConfig.get<boolean>('snapshots.enabled', false)).thenReturn(false);
+            when(mockConfig.get<boolean>('snapshots.enabled', true)).thenReturn(false);
             when(mockedVSCodeNamespaces.workspace.getConfiguration('deepnote')).thenReturn(instance(mockConfig));
 
             const result = service.isSnapshotsEnabled();
@@ -1007,7 +1007,7 @@ project:
             test('should detect Run All when all code cells are executed', async () => {
                 // Set up mocks
                 const mockConfig = mock<WorkspaceConfiguration>();
-                when(mockConfig.get<boolean>('snapshots.enabled', false)).thenReturn(true);
+                when(mockConfig.get<boolean>('snapshots.enabled', true)).thenReturn(true);
                 when(mockedVSCodeNamespaces.workspace.getConfiguration('deepnote')).thenReturn(instance(mockConfig));
 
                 const projectId = 'test-project-id';