Eight catalog entity types have no filter

[jzonthemtn]

Eight catalog entity types have no filter, so REDACT <entity> WITH ... compiles and then detects nothing: CITY, COUNTY, FIRST_NAME, HOSPITAL, PHONE_NUMBER_EXTENSION, STATE, STATE_ABBREVIATION, and SURNAME.

MEDICAL_CONDITION is also unimplemented here but is deliberately excluded: philterd/phisql#41 proposes removing it from the spec.

Acceptance Criteria

• Each of the eight entities has a filter registered in _BUILTIN_FILTERS.
• The dictionary-backed entities reuse the existing dictionary filter machinery.
• A policy naming an entity this engine cannot detect is reported rather than silently inert.

[jzonthemtn]

Closes a gap against the PhiSQL specification. No RFC: these are catalog entities in spec/v1.0/catalog/entity-types.yaml. philterd/phisql#35 is the precedent to weigh against implementing them: an entity no runtime honors gets removed from the spec for having no portable behavior.

[jzonthemtn]

Narrowed from nine entities to eight: MEDICAL_CONDITION is dropped from the scope here because philterd/phisql#41 proposes removing it from the spec rather than implementing it in the runtimes. The earlier comment on this issue lists it as in scope; that is superseded.