Add whole-factory HVAC requirement and process traceability spec

- facility-security.md: continuous temperature/humidity/PM control, zoned
  filtration, burning-season PM2.5 design point, HVAC in PV/battery sizing
- traceability.md: end-to-end per-order customer traceability, batch
  genealogy, log-at-source principles, machine data access as a
  procurement requirement

README.md

@@ -68,8 +68,12 @@ The detail lives in dedicated documents:
 - [Worker safety](docs/worker-safety.md): safety training, galvanics clean
   rooms and decontamination, PPE
 - [Facility security and site systems](docs/facility-security.md): access
-  control, CCTV, archive and audio protection, fire and life safety, plant
-  monitoring, Thai compliance anchors
+  control, CCTV, whole-factory HVAC (temperature, humidity, PM), archive and
+  audio protection, fire and life safety, plant monitoring, Thai compliance
+  anchors
+- [Process logging and traceability](docs/traceability.md): end-to-end
+  per-order traceability for customers, batch genealogy from audio file to
+  shipment, and the requirements this sets for the factory software
 
 ## Repository Layout
 
@@ -82,8 +86,9 @@ docs/
 │   └── pressing-line.md   Press fleet strategy and equipment plan
 ├── finance/               Project cost overviews
 ├── suppliers/             Supplier contacts, vendor landscape, supplier map
-├── facility-security.md   Security, fire and life safety, compliance
+├── facility-security.md   Security, HVAC, fire and life safety, compliance
 ├── sustainability.md      Energy, water, materials commitments
+├── traceability.md        Process logging and per-order traceability
 └── worker-safety.md       Training, clean rooms, PPE
 ```