feat(sandbox): per-agent docker setupCommand

src/config/types.ts

@@ -617,6 +617,11 @@ export type RoutingConfig = {
         /** Legacy alias for scope ("session" when true, "shared" when false). */
         perSession?: boolean;
         workspaceRoot?: string;
+        /** Docker-specific sandbox overrides for this agent. */
+        docker?: {
+          /** Optional setup command run once after container creation. */
+          setupCommand?: string;
+        };
         /** Tool allow/deny policy for sandboxed sessions (deny wins). */
         tools?: {
           allow?: string[];

src/config/zod-schema.ts

@@ -265,6 +265,11 @@ const RoutingSchema = z
                   .optional(),
                 perSession: z.boolean().optional(),
                 workspaceRoot: z.string().optional(),
+                docker: z
+                  .object({
+                    setupCommand: z.string().optional(),
+                  })
+                  .optional(),
                 tools: z
                   .object({
                     allow: z.array(z.string()).optional(),