fix(server): port #13368 to V2 — OpenCode names its own sessions

OpenCode generates a session title from the first prompt only when
session.create leaves the title unset (SessionPrompt.ensureTitle). Main
stopped forwarding prompt-seeded titles from the V1 ProviderCommandReactor,
which V2 deleted. V2's OpenCode adapter sent a placeholder title,
"T3 Code <threadId>", on every session.create, so every V2 OpenCode
session in OpenCode's own UI and history was named after an id.

session.create no longer sends a title. Main also forwards a title the
user renamed by hand. V2 has no title-provenance field on the thread and
never sent the thread title, so that part is left out.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: juliusmarminge

apps/server/src/orchestration-v2/Adapters/OpenCodeAdapterV2.test.ts

@@ -1944,6 +1944,7 @@ describe("OpenCodeAdapterV2", () => {
       const idAllocator = yield* IdAllocatorV2;
       const serverConfig = yield* ServerConfig;
       let createCount = 0;
+      const createInputs: Array<unknown> = [];
       const fakeClient = {
         event: {
           subscribe: async (_input?: unknown, options?: { readonly signal?: AbortSignal }) => ({
@@ -1961,8 +1962,9 @@ describe("OpenCodeAdapterV2", () => {
           }),
         },
         session: {
-          create: async () => {
+          create: async (input: unknown) => {
             createCount += 1;
+            createInputs.push(input);
             return { data: { id: `ses_native_${createCount}`, time: { created: 1, updated: 1 } } };
           },
         },
@@ -2038,6 +2040,11 @@ describe("OpenCodeAdapterV2", () => {
       });
       assert.notEqual(minted.id, placeholder.id);
       assert.equal(minted.nativeThreadRef?.nativeId, "ses_native_2");
+      // OpenCode names a session from its first prompt only when create
+      // leaves the title unset, so the adapter never sends one.
+      for (const input of createInputs) {
+        assert.notProperty(input, "title");
+      }
     }).pipe(
       Effect.scoped,
       Effect.provide(

apps/server/src/orchestration-v2/Adapters/OpenCodeAdapterV2.ts

@@ -3117,15 +3117,13 @@ export function makeOpenCodeAdapterV2(options: OpenCodeAdapterV2Options): Provid
                   providerThread: threadInput.existingProviderThread,
                 });
               }
+              // No title: OpenCode generates one from the first prompt only when
+              // session.create leaves it unset (SessionPrompt.ensureTitle).
               const response = yield* sdkCall(
                 "session.create",
-                {
-                  title: `T3 Code ${threadInput.threadId}`,
-                  permission: openCodePermissionRules(threadInput.runtimePolicy),
-                },
+                { permission: openCodePermissionRules(threadInput.runtimePolicy) },
                 () =>
                   client.session.create({
-                    title: `T3 Code ${threadInput.threadId}`,
                     permission: openCodePermissionRules(threadInput.runtimePolicy),
                   }),
               );