Refactor documentation and diagrams for web/pipeline. (#272)

Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com> for assistance with diagram creation and documentation prose updates.

docs/web/diagrams/database-schema/location.mmd

@@ -0,0 +1,36 @@
+erDiagram
+    Country ||--o{ StateProvince : "has"
+    StateProvince ||--o{ City : "has"
+    City ||--o{ BreweryLoc : "located in"
+
+    %% Cross-schema: defined in full in brewery.mmd
+    Brewery ||--o| BreweryLoc : "has location"
+
+    Country {
+        uniqueidentifier CountryID PK
+        nvarchar CountryName
+        char ISO3166_1 UK
+    }
+
+    StateProvince {
+        uniqueidentifier StateProvinceID PK
+        nvarchar StateProvinceName
+        char ISO3166_2 UK
+        uniqueidentifier CountryID FK
+    }
+
+    City {
+        uniqueidentifier CityID PK
+        nvarchar CityName
+        uniqueidentifier StateProvinceID FK
+    }
+
+    BreweryLoc {
+        uniqueidentifier BreweryPostLocationID PK
+        uniqueidentifier BreweryPostID "FK, UK"
+        nvarchar AddressLine1
+        nvarchar AddressLine2 "nullable"
+        nvarchar PostalCode
+        uniqueidentifier CityID FK
+        geography Coordinates "nullable"
+    }