飞控-77: 74 std flight-controller projects ingested

Topic-pull from local listing index (`name OR introduction` contains
飞控). 77 std hits in oshwhub_listing_full.jsonl, minus 2 already
crawled = 75 attempted; 74 OK + 1 hard fail (`m1_mh743_ada_v4`,
listing entry missing `count.like`).

dev1 walltime: Step 1 ~12s, Step 4 ~80s (concurrency=5).
License mix: 65% GPL 3.0, 11% Public Domain, 11% MIT, 4% CC variants.

3 partial dirs (Step 1 KeyError on missing `count.like`) dropped — to
be re-fetched after a follow-up crawler patch makes count fields
defensive against listing-index outliers.

Source backfill 74/74 OK, total +46 MB.

data/raw/oshwhub/246a02b1831c454a9d7ad54e148d7986/_urls.json

@@ -0,0 +1,16 @@
+{
+  "detail_url": "https://oshwhub.com/cai20070410/f405-huo-jian-fei-kong-50-63",
+  "cover_url": "https://image.lceda.cn/oshwhub/d5c195d383d54475a49471749c017a70.jpg",
+  "attachments": [
+    {
+      "name": "Generic 2400 True Diversity PA.json",
+      "url": "https://image.lceda.cn/oshwhub/project/attachments/7d173d7d3f1145a1a5133bc29d11df79.json",
+      "original_id": "dd764ae90d0049889d0f37def7b63b93"
+    },
+    {
+      "name": "arducopter_with_bl.hex",
+      "url": "https://image.lceda.cn/oshwhub/project/attachments/ce861c47e2ba4c04bdea946598b37fb0.hex",
+      "original_id": "792ce12cdc434139ab20fd663eb3b3f8"
+    }
+  ]
+}