fix(opencode): enforce storage path invariants (#29666)

packages/opencode/test/project/migrate-global.test.ts

@@ -4,6 +4,7 @@ import { Database } from "@opencode-ai/core/database/database"
 import { eq } from "drizzle-orm"
 import { SessionTable } from "@opencode-ai/core/session/sql"
 import { ProjectTable } from "@opencode-ai/core/project/sql"
+import { AbsolutePath } from "@opencode-ai/core/schema"
 import { ProjectV2 } from "@opencode-ai/core/project"
 import { SessionID } from "../../src/session/schema"
 import * as Log from "@opencode-ai/core/util/log"
@@ -48,7 +49,7 @@ function ensureGlobal() {
       .insert(ProjectTable)
       .values({
         id: ProjectV2.ID.global,
-        worktree: "/",
+        worktree: AbsolutePath.make("/"),
         time_created: Date.now(),
         time_updated: Date.now(),
         sandboxes: [],