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/a670e60acee54566a9f3e841bb634274/source/manifest.json

@@ -0,0 +1,45 @@
+{
+  "project_uuid": "a670e60acee54566a9f3e841bb634274",
+  "fetched_at": "2026-04-28T17:55:01.674475+00:00",
+  "editor_version": "2.1.32.5533625a",
+  "boards": [
+    {
+      "sch": "e178f68586704163a8dccbc5fd3721e4",
+      "name": "逐梦壹号STC32智能小车 V1.2",
+      "pcb": "315de6a9f4c54b9ab09c5f86f5a7ea85"
+    }
+  ],
+  "documents": [
+    {
+      "doc_uuid": "6ac18fdc8ba44e209bbeae6bb4c4ccc9",
+      "docType": 1,
+      "path": "source/6ac18fdc8ba44e209bbeae6bb4c4ccc9.json",
+      "size": 81109,
+      "sha256": "6deaa64c5f97f28845407a421164c48aa06ed1796036020730aa51c65781991d"
+    },
+    {
+      "doc_uuid": "315de6a9f4c54b9ab09c5f86f5a7ea85",
+      "docType": 3,
+      "path": "source/pcb_315de6a9f4c54b9ab09c5f86f5a7ea85.json",
+      "size": 178930,
+      "sha256": "6c2a4f2a603ffc5ddfe49a14880c81ce6099d837e1d4c6cc27480b4d374fe1fe"
+    }
+  ],
+  "structure_summary": {
+    "boards": 1,
+    "schematic_containers": 1,
+    "schematic_sheets": 1,
+    "pcbs": 1,
+    "symbols": 42,
+    "footprints": 85,
+    "devices": 126,
+    "coppers": 8,
+    "textpath": 8,
+    "blobs": 7
+  },
+  "aux": {
+    "coppers_count": 0,
+    "textpath_count": 8,
+    "blobs_count": 7
+  }
+}