this derivation will be built:
  /nix/store/r6z6vzzjgynb15ack9gbaxyy9xqv8m6a-treefmt-check.drv
building '/nix/store/r6z6vzzjgynb15ack9gbaxyy9xqv8m6a-treefmt-check.drv'
treefmt-check> treefmt v2.6.0traversed 569 files
treefmt-check> emitted 377 files for processing
treefmt-check> formatted 377 files (1 changed) in 834ms
treefmt-check>  M packages/spaces-integration-gateway/gateway-core.ts
treefmt-check> diff --git a/packages/spaces-integration-gateway/gateway-core.ts b/packages/spaces-integration-gateway/gateway-core.ts
treefmt-check> index 2fac038..94e9c0d 100644
treefmt-check> --- a/packages/spaces-integration-gateway/gateway-core.ts
treefmt-check> +++ b/packages/spaces-integration-gateway/gateway-core.ts
treefmt-check> @@ -113,8 +113,7 @@ export interface McpStep {
treefmt-check>  }
treefmt-check>  
treefmt-check>  export type McpExchangeResult =
treefmt-check> -  | { ok: true; reply: Record<string, unknown> }
treefmt-check> -  | { ok: false; reason: string };
treefmt-check> +  { ok: true; reply: Record<string, unknown> } | { ok: false; reason: string };
treefmt-check>  
treefmt-check>  /**
treefmt-check>   * One MCP exchange on a fresh unix-socket connection, the "MCP wire". It speaks
error: Cannot build '/nix/store/r6z6vzzjgynb15ack9gbaxyy9xqv8m6a-treefmt-check.drv'.
       Reason: builder failed with exit code 1.
       Output paths:
         /nix/store/gd9628mw65valc1gsn67cixv0rr2x10g-treefmt-check
       Last 18 log lines:
       > treefmt v2.6.0traversed 569 files
       > emitted 377 files for processing
       > formatted 377 files (1 changed) in 834ms
       >  M packages/spaces-integration-gateway/gateway-core.ts
       > diff --git a/packages/spaces-integration-gateway/gateway-core.ts b/packages/spaces-integration-gateway/gateway-core.ts
       > index 2fac038..94e9c0d 100644
       > --- a/packages/spaces-integration-gateway/gateway-core.ts
       > +++ b/packages/spaces-integration-gateway/gateway-core.ts
       > @@ -113,8 +113,7 @@ export interface McpStep {
       >  }
       >  
       >  export type McpExchangeResult =
       > -  | { ok: true; reply: Record<string, unknown> }
       > -  | { ok: false; reason: string };
       > +  { ok: true; reply: Record<string, unknown> } | { ok: false; reason: string };
       >  
       >  /**
       >   * One MCP exchange on a fresh unix-socket connection, the "MCP wire". It speaks
       For full logs, run:
         nix log /nix/store/r6z6vzzjgynb15ack9gbaxyy9xqv8m6a-treefmt-check.drv