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/ddcc963f6e234ee5b25bdf62d13c4a6b/metadata.json

@@ -109,5 +109,31 @@
     "public": true,
     "publish": true,
     "skipped_files": []
-  }
+  },
+  "source_format": "easyeda-pro-legacy",
+  "source_path": "source/",
+  "source_documents": [
+    {
+      "doc_uuid": "3e554def317b43e4992f8ed77dfd72ef",
+      "docType": 1,
+      "path": "source/3e554def317b43e4992f8ed77dfd72ef.json",
+      "size": 814,
+      "sha256": "b47b1f0a772042141b1c9ac23b0f86d0a115e0ae6af625e4dc3f57435a2916fb"
+    },
+    {
+      "doc_uuid": "35ada97816214389888841096021007d",
+      "docType": 1,
+      "path": "source/35ada97816214389888841096021007d.json",
+      "size": 796,
+      "sha256": "a09df497ba4d109449ab433a22335232763090b0993e61382de1d5b6a02c4252"
+    },
+    {
+      "doc_uuid": "2c2c91b7abd94776b2d20b6101d6d843",
+      "docType": 3,
+      "path": "source/pcb_2c2c91b7abd94776b2d20b6101d6d843.json",
+      "size": 768,
+      "sha256": "2b5625b1ed710c1c27636a5db17e88854d68ecd508a013b75bb6b9110f14b201"
+    }
+  ],
+  "editor_version": "2.2.21.2"
 }