feat(CC-068): add data_sources table (migration 0014)

drizzle/0014_data_sources.sql

@@ -0,0 +1,15 @@
+-- CC-068: data_sources registry
+CREATE TABLE IF NOT EXISTS "data_sources" (
+  "id"              uuid DEFAULT gen_random_uuid() PRIMARY KEY NOT NULL,
+  "tenant_id"       uuid NOT NULL,
+  "name"            text NOT NULL,
+  "source_type"     text DEFAULT 'manual' NOT NULL,
+  "description"     text,
+  "connection_info" text,
+  "status"          text DEFAULT 'active' NOT NULL,
+  "last_sync_at"    timestamp,
+  "record_count"    integer,
+  "tags"            text[] DEFAULT '{}' NOT NULL,
+  "created_at"      timestamp DEFAULT now() NOT NULL,
+  "updated_at"      timestamp DEFAULT now() NOT NULL
+);