revert backend changes, keep only frontend clone fixes

Avoids pathological cases when cloning large objects

Fixes #14344

packages/opencode/src/cli/cmd/tui/component/prompt/history.tsx

@@ -3,7 +3,6 @@ import { Global } from "@/global"
 import { Filesystem } from "@/util/filesystem"
 import { onMount } from "solid-js"
 import { createStore, produce } from "solid-js/store"
-import { clone } from "remeda"
 import { createSimpleContext } from "../../context/helper"
 import { appendFile, writeFile } from "fs/promises"
 import type { AgentPart, FilePart, TextPart } from "@opencode-ai/sdk/v2"
@@ -83,7 +82,7 @@ export const { use: usePromptHistory, provider: PromptHistoryProvider } = create
         return store.history.at(store.index)
       },
       append(item: PromptInfo) {
-        const entry = clone(item)
+        const entry = structuredClone(item)
         let trimmed = false
         setStore(
           produce((draft) => {

packages/opencode/src/cli/cmd/tui/component/prompt/stash.tsx

@@ -3,7 +3,6 @@ import { Global } from "@/global"
 import { Filesystem } from "@/util/filesystem"
 import { onMount } from "solid-js"
 import { createStore, produce } from "solid-js/store"
-import { clone } from "remeda"
 import { createSimpleContext } from "../../context/helper"
 import { appendFile, writeFile } from "fs/promises"
 import type { PromptInfo } from "./history"
@@ -53,7 +52,7 @@ export const { use: usePromptStash, provider: PromptStashProvider } = createSimp
         return store.entries
       },
       push(entry: Omit<StashEntry, "timestamp">) {
-        const stash = clone({ ...entry, timestamp: Date.now() })
+        const stash = structuredClone({ ...entry, timestamp: Date.now() })
         let trimmed = false
         setStore(
           produce((draft) => {

packages/opencode/src/session/llm.ts

@@ -210,18 +210,12 @@ export namespace LLM {
       maxOutputTokens,
       abortSignal: input.abort,
       headers: {
-        ...(input.model.providerID.startsWith("opencode")
-          ? {
-              "x-opencode-project": Instance.project.id,
-              "x-opencode-session": input.sessionID,
-              "x-opencode-request": input.user.id,
-              "x-opencode-client": Flag.OPENCODE_CLIENT,
-            }
-          : input.model.providerID !== "anthropic"
-            ? {
-                "User-Agent": `opencode/${Installation.VERSION}`,
-              }
-            : undefined),
+        ...(input.model.providerID.startsWith("opencode") && {
+          "x-opencode-project": Instance.project.id,
+          "x-opencode-session": input.sessionID,
+          "x-opencode-request": input.user.id,
+          "x-opencode-client": Flag.OPENCODE_CLIENT,
+        }),
         ...input.model.headers,
         ...headers,
       },