feat: move diff_style from config to kv.json and add toggle menu

packages/opencode/src/cli/cmd/tui/app.tsx

@@ -570,6 +570,16 @@ function App() {
         dialog.clear()
       },
     },
+    {
+      title: kv.get("diff_style", "auto") === "auto" ? "Use unified diff style" : "Use automatic diff style",
+      value: "tui.diff_style.toggle",
+      category: "System",
+      onSelect: (dialog) => {
+        const current = kv.get("diff_style", "auto")
+        kv.set("diff_style", current === "auto" ? "unified" : "auto")
+        dialog.clear()
+      },
+    },
   ])
 
   createEffect(() => {

packages/opencode/src/cli/cmd/tui/routes/session/index.tsx

@@ -1819,11 +1819,12 @@ function Task(props: ToolProps<typeof TaskTool>) {
 
 function Edit(props: ToolProps<typeof EditTool>) {
   const ctx = use()
+  const kv = useKV()
   const { theme, syntax } = useTheme()
 
   const view = createMemo(() => {
-    const diffStyle = ctx.sync.data.config.tui?.diff_style
-    if (diffStyle === "stacked") return "unified"
+    const diffStyle = kv.get("diff_style", "auto")
+    if (diffStyle === "unified") return "unified"
     // Default to "auto" behavior
     return ctx.width > 120 ? "split" : "unified"
   })
@@ -1888,13 +1889,14 @@ function Edit(props: ToolProps<typeof EditTool>) {
 
 function ApplyPatch(props: ToolProps<typeof ApplyPatchTool>) {
   const ctx = use()
+  const kv = useKV()
   const { theme, syntax } = useTheme()
 
   const files = createMemo(() => props.metadata.files ?? [])
 
   const view = createMemo(() => {
-    const diffStyle = ctx.sync.data.config.tui?.diff_style
-    if (diffStyle === "stacked") return "unified"
+    const diffStyle = kv.get("diff_style", "auto")
+    if (diffStyle === "unified") return "unified"
     return ctx.width > 120 ? "split" : "unified"
   })
 

packages/opencode/src/cli/cmd/tui/routes/session/permission.tsx

@@ -8,6 +8,7 @@ import type { PermissionRequest } from "@opencode-ai/sdk/v2"
 import { useSDK } from "../../context/sdk"
 import { SplitBorder } from "../../component/border"
 import { useSync } from "../../context/sync"
+import { useKV } from "../../context/kv"
 import { useTextareaKeybindings } from "../../component/textarea-keybindings"
 import path from "path"
 import { LANGUAGE_EXTENSIONS } from "@/lsp/language"
@@ -48,15 +49,15 @@ function EditBody(props: { request: PermissionRequest }) {
   const themeState = useTheme()
   const theme = themeState.theme
   const syntax = themeState.syntax
-  const sync = useSync()
+  const kv = useKV()
   const dimensions = useTerminalDimensions()
 
   const filepath = createMemo(() => (props.request.metadata?.filepath as string) ?? "")
   const diff = createMemo(() => (props.request.metadata?.diff as string) ?? "")
 
   const view = createMemo(() => {
-    const diffStyle = sync.data.config.tui?.diff_style
-    if (diffStyle === "stacked") return "unified"
+    const diffStyle = kv.get("diff_style", "auto")
+    if (diffStyle === "unified") return "unified"
     return dimensions().width > 120 ? "split" : "unified"
   })
 

packages/opencode/src/config/config.ts

@@ -806,10 +806,6 @@ export namespace Config {
       })
       .optional()
       .describe("Scroll acceleration settings"),
-    diff_style: z
-      .enum(["auto", "stacked"])
-      .optional()
-      .describe("Control diff rendering style: 'auto' adapts to terminal width, 'stacked' always shows single column"),
   })
 
   export const Server = z