chore: add config file merging, wildcard anonymization, and secure file output

[nabroleonx]

• Config file support: full YAML config parsing with CLI override precedence, per-table overrides (skip, depth, direction, max_rows), and deprecated key aliases (include_drop_tables -> include_truncate)
• Wildcard anonymization: glob-based patterns for table.column matching with exact > wildcard > builtin precedence, custom field providers, and security_null_fields wildcards
• Secure file I/O: new fileio.py with os.open/fchmod for deterministic permissions, --output-file-mode CLI flag, applied to all output paths
• Row limits: max_rows_per_table with deterministic PK-sorted selection and parent closure to preserve FK integrity
• Per-table traversal: table-specific depth and direction overrides in BFS graph traversal
• CLI: all boolean flags support --no-* variants, proper None defaults for config merging, dynamic version from package metadata
• PostgreSQL adapter: sync per-table FK lists with graph edges, simplify batch fetching
• Docs and tests updated for all new features