test: define schema contract for topic fact graph

src/core/schema.ts

@@ -0,0 +1,34 @@
+export const TOPICS_TABLE = 'topics';
+export const FACTS_TABLE = 'facts';
+export const FACT_TOPICS_TABLE = 'fact_topics';
+
+export const TOPIC_COLUMNS = [
+  'id',
+  'name',
+  'normalized_name',
+  'category',
+  'granularity',
+  'description',
+  'metadata',
+  'created_at',
+  'updated_at',
+] as const;
+
+export const FACT_COLUMNS = [
+  'id',
+  'statement',
+  'summary',
+  'source',
+  'confidence',
+  'metadata',
+  'created_at',
+  'updated_at',
+] as const;
+
+export const FACT_TOPIC_COLUMNS = [
+  'fact_id',
+  'topic_id',
+  'role',
+  'position',
+  'created_at',
+] as const;