fix(agent): preserve runtime request context

OpenCode tools run in a child service, so they cannot read the Agent process-local session map. Hydrate a sanitized context through the authenticated internal bridge and centralize backend project headers to prevent context loss across both boundaries.

.opencode/tools/memory_manager.ts

@@ -1,9 +1,8 @@
 import { tool } from "@opencode-ai/plugin";
+
 import { MemoryStore } from "../../src/memory/store.js";
-import {
-  getRuntimeSessionContext,
-  setRuntimeSessionContext,
-} from "../../src/runtime/sessionContext.js";
+import { readBridgedRuntimeSessionContext } from "../../src/runtime/internalSessionContextBridge.js";
+import { setRuntimeSessionContext } from "../../src/runtime/sessionContext.js";
 
 const memoryStore = new MemoryStore();
 const initializePromise = memoryStore.initialize();
@@ -36,7 +35,9 @@ export default tool({
   },
   async execute(args, context) {
     await initializePromise;
-    const sessionContext = getRuntimeSessionContext(context.sessionID);
+    const sessionContext = await readBridgedRuntimeSessionContext(
+      context.sessionID,
+    );
     if (!sessionContext) {
       throw new Error(`session context not found for ${context.sessionID}`);
     }