composition skeleton: L1 accounting domain + six L2 function-group packages

Step 2 of the vk-gramatvediba build (absorbs the planned Step 3 — the
enterprise index now references the domain, since the two are one
coherent unit).

- domains/gramatvediba/ — L1 domain package; includes the six FG packages
- processes/fg1..fg6/ — six L2 function-group packages (composition stubs;
  FG3 carries its sub-process inventory and is taken to executable depth
  in later steps)
- each package: uapf.yaml + metadata/ownership.yaml + metadata/lifecycle.yaml
  + README
- enterprise/enterprise.yaml now references the L1 domain

All 22 manifests and metadata files validate against the UAPF 2.2.0
schemas; all seven includes / enterprise references resolve.

domains/gramatvediba/README.md

@@ -0,0 +1,17 @@
+# Grāmatvedības uzskaite — accounting domain (L1)
+
+Level 1 domain package. Composes the six Valsts Kase / Vienotais pakalpojumu
+centrs (VPC) accounting function groups via the manifest `includes` field.
+
+| FG | Function group |
+|----|----------------|
+| FG1 | Ilgtermiņa nefinanšu aktīvu un krājumu uzskaite |
+| FG2 | Finanšu aktīvu uzskaite |
+| FG3 | Saistību un izdevumu uzskaite |
+| FG4 | Saistību par atlīdzību uzskaite |
+| FG5 | Prasību un ieņēmumu uzskaite |
+| FG6 | Pārskatu sagatavošana publiskošanai |
+
+Each function group is an L2 package under `processes/`. FG3 is taken to
+executable (L4) depth in this proof-of-concept; the others are composition
+stubs.