batch-50: Step 3-4 source download from Guangzhou — 49/50 ok

Run on dev1 (Guangzhou) for the latency advantage. Walltime 3:41 vs
Singapore-estimated 1-2h (~30x speedup, mostly from image.lceda.cn
RTT going from 263ms to 2.6ms).

Pro 25:  24 ok + 1 fail (Super Dial 7f7565ef11 — Pro 2.x legacy
                          schematic/lists 401, separate cookie-perm issue)
         611 docs, 31 MB total
Std 25:  25 ok, 97 docs, 74 MB total
Combined: 49/50 success, 708 docs, 105 MB new disk usage

--max-source-mb 200 cap was not tripped; the 25 Pro candidates are all
under 10 MB, so the 481 MB X86-board outlier from the original sample
was not representative.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

data/raw/oshwhub/53e6c236b9d14e74944e460ac11c7c1d/metadata.json

@@ -91,5 +91,31 @@
     "public": true,
     "publish": true,
     "skipped_files": []
-  }
+  },
+  "source_format": "easyeda-pro-legacy",
+  "source_path": "source/",
+  "source_documents": [
+    {
+      "doc_uuid": "dc7c6b0a79e742f9995551d33f26dee6",
+      "docType": 1,
+      "path": "source/dc7c6b0a79e742f9995551d33f26dee6.json",
+      "size": 135974,
+      "sha256": "7dcb5c1110cf8136c09488c988d31ac814237d5a4eaf3c867fb3692edd956043"
+    },
+    {
+      "doc_uuid": "fa2e0555acf44dc39c367652c4da28e7",
+      "docType": 1,
+      "path": "source/fa2e0555acf44dc39c367652c4da28e7.json",
+      "size": 64265,
+      "sha256": "0bacef652eb8b16b804bc740e7638b8c34fd2418c587e6858eac2df1667cf4c6"
+    },
+    {
+      "doc_uuid": "0e29a50ddd1946bab5f24f135c76ca25",
+      "docType": 3,
+      "path": "source/pcb_0e29a50ddd1946bab5f24f135c76ca25.json",
+      "size": 155537,
+      "sha256": "589865ae1a201ab416b0d408eb0155f460b6fd89e35652487648c42cff96f128"
+    }
+  ],
+  "editor_version": "2.1.32.5533625a.f972c4"
 }