fix(qoder): report usage to all clients and stop inlining large attachments

- Coalesce Qoder's empty finish-in-delta frame with the later choices:[] usage
  frame so OpenAI and Claude clients receive prompt_tokens, completion_tokens
  and cache-hit tokens (the dashboard already saw them)
- Upload inlined images through /api/v2/image/upload like qodercli, and stub
  oversized non-image files instead of stuffing 30MB+ data URIs into
  agent_chat_generation
- Emit response.completed -> response.usage for chat-native upstreams so
  /v1/responses clients (Codex CLI, sub2api) no longer log 0/0/0
- Keep Claude message_delta.usage working when usage arrives without choices[0]
- Escalate to the smallest advertised Qoder context tier (200K/400K/1M) when
  the estimated prompt no longer fits max_input_tokens
- Pass apiKey for PAT connections and list hidden enable:false catalog keys
  from /v1/models

open-sse/transformer/responsesTransformer.js

@@ -6,6 +6,7 @@
 
 import fs from "fs";
 import path from "path";
+import { toResponsesUsage } from "../translator/concerns/usage.js";
 
 // Create log directory for responses (Node.js only)
 export function createResponsesLogger(model, logsDir = null) {
@@ -73,6 +74,7 @@ export function createResponsesApiTransformStream(logger = null) {
     funcArgsDone: {},
     funcItemDone: {},
     buffer: "",
+    usage: null,
     completedSent: false
   };
 
@@ -225,17 +227,17 @@ export function createResponsesApiTransformStream(logger = null) {
   const sendCompleted = (controller) => {
     if (!state.completedSent) {
       state.completedSent = true;
-      emit(controller, "response.completed", {
-        type: "response.completed",
-        response: {
-          id: state.responseId,
-          object: "response",
-          created_at: state.created,
-          status: "completed",
-          background: false,
-          error: null
-        }
-      });
+      const response = {
+        id: state.responseId,
+        object: "response",
+        created_at: state.created,
+        status: "completed",
+        background: false,
+        error: null
+      };
+      const usage = toResponsesUsage(state.usage);
+      if (usage) response.usage = usage;
+      emit(controller, "response.completed", { type: "response.completed", response });
     }
   };
 
@@ -264,6 +266,9 @@ export function createResponsesApiTransformStream(logger = null) {
           continue;
         }
 
+        // Remember usage (finish chunk or trailing include_usage frame) for response.completed
+        if (parsed.usage && typeof parsed.usage === "object") state.usage = parsed.usage;
+
         if (!parsed.choices?.length) continue;
         
         const choice = parsed.choices[0];