fix microsoft#199662 (microsoft#199667)

Author: jrieken

src/vs/workbench/contrib/inlineChat/browser/inlineChatActions.ts

@@ -43,7 +43,7 @@ export class StartSessionAction extends EditorAction2 {
 			title: { value: LOCALIZED_START_INLINE_CHAT_STRING, original: 'Start Inline Chat' },
 			category: AbstractInlineChatAction.category,
 			f1: true,
-			precondition: CTX_INLINE_CHAT_HAS_PROVIDER,
+			precondition: ContextKeyExpr.and(CTX_INLINE_CHAT_HAS_PROVIDER, EditorContextKeys.writable),
 			keybinding: {
 				when: EditorContextKeys.focus,
 				weight: KeybindingWeight.WorkbenchContrib,