fix: hide empty intermediate assistant messages in TUI

When using the Responses API, intermediate assistant messages with
finish reason "other" were rendering empty footer bars and blank
space. Two changes:

1. Add "other" to the excluded finish reasons in final() to align
   with the prompt loop logic that treats "other" as non-terminal.

2. Add a reactive visible() memo that hides the entire
   AssistantMessage when no parts would render and no footer/error
   is shown.

Author: kostiantyn-kugot

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

@@ -1349,7 +1349,7 @@ function AssistantMessage(props: { message: AssistantMessage; parts: Part[]; las
   const model = createMemo(() => Model.name(ctx.providers(), props.message.providerID, props.message.modelID))
 
   const final = createMemo(() => {
-    return props.message.finish && !["tool-calls", "unknown"].includes(props.message.finish)
+    return props.message.finish && !["tool-calls", "unknown", "other"].includes(props.message.finish)
   })
 
   const duration = createMemo(() => {
@@ -1362,8 +1362,28 @@ function AssistantMessage(props: { message: AssistantMessage; parts: Part[]; las
 
   const keybind = useKeybind()
 
+  const footer = createMemo(
+    () => props.last || final() || props.message.error?.name === "MessageAbortedError",
+  )
+
+  const visible = createMemo(() => {
+    if (footer()) return true
+    if (props.message.error && props.message.error.name !== "MessageAbortedError") return true
+    for (const part of props.parts) {
+      if (part.type === "text" && (part as TextPart).text.trim()) return true
+      if (part.type === "tool" && (ctx.showDetails() || (part as ToolPart).state.status !== "completed")) return true
+      if (
+        part.type === "reasoning" &&
+        ctx.showThinking() &&
+        (part as ReasoningPart).text.replace("[REDACTED]", "").trim()
+      )
+        return true
+    }
+    return false
+  })
+
   return (
-    <>
+    <Show when={visible()}>
       <For each={props.parts}>
         {(part, index) => {
           const component = createMemo(() => PART_MAPPING[part.type as keyof typeof PART_MAPPING])
@@ -1402,7 +1422,7 @@ function AssistantMessage(props: { message: AssistantMessage; parts: Part[]; las
         </box>
       </Show>
       <Switch>
-        <Match when={props.last || final() || props.message.error?.name === "MessageAbortedError"}>
+        <Match when={footer()}>
           <box paddingLeft={3}>
             <text marginTop={1}>
               <span
@@ -1427,7 +1447,7 @@ function AssistantMessage(props: { message: AssistantMessage; parts: Part[]; las
           </box>
         </Match>
       </Switch>
-    </>
+    </Show>
   )
 }