Adopt UAPF v2.0.0 cornerstone naming: .bpmn.xml/.dmn.xml -> .bpmn/.dmn

UAPF-specification v2.0.0 mandates OMG-standard cornerstone extensions.
Renamed cornerstone files and updated references in README / docs /
processgit.mcp.yaml. Content of the BPMN/DMN files is unchanged.

README.md

@@ -88,11 +88,11 @@ lv.tiesibsargs.iesnieguma-izskatisana/
 ├── manifest.json
 ├── README.md                              (this file)
 ├── bpmn/
-│   └── iesnieguma-izskatisana.bpmn.xml    Process flow (linear, 10 nodes)
+│   └── iesnieguma-izskatisana.bpmn    Process flow (linear, 10 nodes)
 ├── dmn/
-│   ├── classify-topic.dmn.xml             9 rules, FIRST hit policy
-│   ├── determine-priority.dmn.xml         6 rules, FIRST hit policy
-│   └── route-to-department.dmn.xml        9 rules, UNIQUE hit policy
+│   ├── classify-topic.dmn             9 rules, FIRST hit policy
+│   ├── determine-priority.dmn         6 rules, FIRST hit policy
+│   └── route-to-department.dmn        9 rules, UNIQUE hit policy
 ├── resources/
 │   ├── guardrails.yaml                    Policy snapshot for session
 │   ├── tiesibsargs-taxonomy.yaml          Canonical topic list + legal anchors

processgit.mcp.yaml

@@ -14,15 +14,15 @@ server:
     The process executes via UAPF-IP; see the /uapf-ip endpoint of this repo.
 
 sources:
-  - path: "bpmn/iesnieguma-izskatisana.bpmn.xml"
+  - path: "bpmn/iesnieguma-izskatisana.bpmn"
     type: "xml"
     description: "BPMN - end-to-end complaint intake and triage flow"
-  - path: "dmn/classify-topic.dmn.xml"
+  - path: "dmn/classify-topic.dmn"
     type: "xml"
     description: "DMN - classifies the complaint topic"
-  - path: "dmn/determine-priority.dmn.xml"
+  - path: "dmn/determine-priority.dmn"
     type: "xml"
     description: "DMN - determines case priority"
-  - path: "dmn/route-to-department.dmn.xml"
+  - path: "dmn/route-to-department.dmn"
     type: "xml"
     description: "DMN - routes the case to the responsible department"