chore: rename ExecutorRuntime → CoreRunner in docs and templates

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: ProtocolWarden

.github/PULL_REQUEST_TEMPLATE.md

@@ -11,7 +11,7 @@
 ## Scope Check
 
 - [ ] Change stays within source resolution + verification (or patch records / reconciliation)
-- [ ] No subprocess execution / runner logic introduced (that's ExecutorRuntime)
+- [ ] No subprocess execution / runner logic introduced (that's CoreRunner)
 - [ ] No routing or planning logic introduced
 - [ ] Force-push and PR-creation consent flags still gate destructive actions
 

CONTRIBUTING.md

@@ -34,7 +34,7 @@ ruff check src/
 
 SourceRegistry intentionally has a narrow scope: **resolve named source dependencies to local paths and verify expected source state**. Do **not** add:
 
-- Subprocess execution or runner logic (that lives in ExecutorRuntime)
+- Subprocess execution or runner logic (that lives in CoreRunner)
 - Scheduling, queues, or workflow orchestration
 - Routing decisions (that lives in SwitchBoard)
 - Planning or proposal logic (that lives in OperationsCenter)

README.md

@@ -16,7 +16,7 @@
 
 - OperationsCenter — orchestration, planning, policy
 - SwitchBoard — lane/backend selection
-- ExecutorRuntime — runtime execution mechanics
+- CoreRunner — runtime execution mechanics
 - CxRP — orchestration contract
 - RxP — runtime contract
 - a scheduler / executor / subprocess runner