fix(tui): resolve wrong provider prefix when session has model without modelProvider (#25874)

Merged via /review-pr -> /prepare-pr -> /merge-pr.

Prepared head SHA: f0953a7284
Co-authored-by: lbo728 <72309817+lbo728@users.noreply.github.com>
Co-authored-by: gumadeiras <5599352+gumadeiras@users.noreply.github.com>
Reviewed-by: @gumadeiras

src/commands/agent/session-store.ts

@@ -4,7 +4,11 @@ import { DEFAULT_CONTEXT_TOKENS } from "../../agents/defaults.js";
 import { isCliProvider } from "../../agents/model-selection.js";
 import { deriveSessionTotalTokens, hasNonzeroUsage } from "../../agents/usage.js";
 import type { OpenClawConfig } from "../../config/config.js";
-import { type SessionEntry, updateSessionStore } from "../../config/sessions.js";
+import {
+  setSessionRuntimeModel,
+  type SessionEntry,
+  updateSessionStore,
+} from "../../config/sessions.js";
 
 type RunResult = Awaited<
   ReturnType<(typeof import("../../agents/pi-embedded.js"))["runEmbeddedPiAgent"]>
@@ -58,10 +62,12 @@ export async function updateSessionStoreAfterAgentRun(params: {
     ...entry,
     sessionId,
     updatedAt: Date.now(),
-    modelProvider: providerUsed,
-    model: modelUsed,
     contextTokens,
   };
+  setSessionRuntimeModel(next, {
+    provider: providerUsed,
+    model: modelUsed,
+  });
   if (isCliProvider(providerUsed, cfg)) {
     const cliSessionId = result.meta.agentMeta?.sessionId?.trim();
     if (cliSessionId) {