fix(B-08,NEW-1): remove duplicate fulltext from SETUP_QUERIES; modern CREATE FULLTEXT INDEX syntax

fix(ascii): replace all non-ASCII chars in Python source files

fix(B-07): CONTESTED_IN relationship target was Scheme, corrected to Constituency

fix(B-05 step2): add Affidavit uniqueness constraint and year index to SETUP_QUERIES

fix(B-05 step1): add Affidavit node and FILED_AFFIDAVIT to schema

fix(BUG-18/19): timeline audit events use entity_name not entity_id; fulltext index covers all 16 node types

fix(search+multilingual+sources): global search, fulltext index, sources API

feat(graph): add Neo4j schema - nodes, relationships, constraints