feat: Migrate MaterialDimensions from TPH to TPC and add Alro catalog seeding

Switch MaterialDimensions inheritance from TPH (single table with discriminator)
to TPC (table per concrete type) with individual tables per shape. Add Swagger
for dev API exploration, expand SeedController with export/import endpoints and
Alro catalog JSON dataset, and include Python scraper for Alro catalog PDFs.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CutList.Web/Data/SeedData/alro-catalog.json

@@ -0,0 +1,31 @@
+{
+  "exportedAt": "2026-02-16T17:09:52.843008+00:00",
+  "suppliers": [
+    {
+      "name": "Alro Steel"
+    }
+  ],
+  "cuttingTools": [
+    {
+      "name": "Bandsaw",
+      "kerfInches": 0.0625,
+      "isDefault": true
+    },
+    {
+      "name": "Chop Saw",
+      "kerfInches": 0.125,
+      "isDefault": false
+    },
+    {
+      "name": "Cold Cut Saw",
+      "kerfInches": 0.0625,
+      "isDefault": false
+    },
+    {
+      "name": "Hacksaw",
+      "kerfInches": 0.0625,
+      "isDefault": false
+    }
+  ],
+  "materials": []
+}