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/b4a490405bbd43b8a7577a8faf4b35c2/metadata.json

@@ -136,5 +136,42 @@
     "public": true,
     "publish": true,
     "skipped_files": []
-  }
+  },
+  "source_format": "easyeda-std",
+  "source_path": "source/",
+  "source_documents": [
+    {
+      "doc_uuid": "634ec706fc064c578e1d7966723f5233",
+      "docType": 1,
+      "master": "743c5828be5a4ca4883191f6ad4a407d",
+      "path": "source/634ec706fc064c578e1d7966723f5233.json",
+      "size": 2941926,
+      "sha256": "8a2290907c093834361d623d362fd8253835c24c26072401367b416d2d74a55d"
+    },
+    {
+      "doc_uuid": "579a730c17664aeaa630da6d82154b55",
+      "docType": 3,
+      "master": "44bde865dcd44c3db7e3e72262efa705",
+      "path": "source/579a730c17664aeaa630da6d82154b55.json",
+      "size": 654271,
+      "sha256": "537b8c8875b9d48fa9b73f13fdb006bc305070fc88791f828a8b9a57832234a3"
+    },
+    {
+      "doc_uuid": "a438e25cb6224351b758466429a398ff",
+      "docType": 1,
+      "master": "197c82af731c4f22aac1634de339bad0",
+      "path": "source/a438e25cb6224351b758466429a398ff.json",
+      "size": 2941926,
+      "sha256": "8a2290907c093834361d623d362fd8253835c24c26072401367b416d2d74a55d"
+    },
+    {
+      "doc_uuid": "06955688414a4d029a0d5fbc05bc1bdd",
+      "docType": 3,
+      "master": "d7bf2ed65b0446a68f62653107b37c25",
+      "path": "source/06955688414a4d029a0d5fbc05bc1bdd.json",
+      "size": 1109464,
+      "sha256": "977a1f7928a482f25b369411b7dadc350902b4940201cd53b219297ac90e4760"
+    }
+  ],
+  "editor_version": "6.5.1"
 }