Revision history: HVAC Instrumentation and Control Devices

Datasheet constraints: every range, checkbox and listbox field now states its direction

Remade from scratch under the authoring cheatsheet: the field-device layer of the building automation system, control valves and pneumatic devices owned here, one enclosure field with the harsher locations as clauses, a trade-off note beside every choice

Corpus sync: neutrality remakes, note hygiene, datasheet relocation, transformer-split cross-refs

Initial publication