feat(0130): kanban_cpp v2 — backend Go + 5 registry parser fns + epic/sub-issues

Registry (issue 0130a):
- 5 fns infra: parse_issue_md, write_issue_md, scan_issues_dir,
  scan_flows_dir, watch_dir_fsnotify
- 3 tipos: Issue, Flow, FsEvent
- Tests round-trip + scan reales + watcher fsnotify (all PASS)
- Capability group 'kanban' nuevo (docs/capabilities/kanban.md)

Apps:
- apps/kanban_cpp/ (sub-repo) — frontend ImGui: board drag-drop,
  flows, filters, detail con CSV editors
- apps/kanban_cpp/backend/ — Go service port 8487: REST + SSE +
  fsnotify watcher, parser bidireccional MD<->SQLite cache

Issues:
- dev/issues/0130-kanban-cpp-v2.md (epic)
- 0130a parser, 0130b backend, 0130c frontend

CMakeLists.txt: add_subdirectory apps/kanban_cpp (registrado por
init_cpp_app scaffolder).

End-to-end verde: backend devuelve 189 issues + 9 flows; PATCH a
/api/issues/{id} reescribe .md (solo frontmatter, body intacto);
frontend --self-test exit 0; tests Go infra 5/5 PASS.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

cpp/CMakeLists.txt

@@ -535,3 +535,9 @@ set(_AGENTS_DASHBOARD_DIR ${CMAKE_SOURCE_DIR}/../projects/element_agents/apps/ag
 if(EXISTS ${_AGENTS_DASHBOARD_DIR}/CMakeLists.txt)
     add_subdirectory(${_AGENTS_DASHBOARD_DIR} ${CMAKE_BINARY_DIR}/apps/agents_dashboard)
 endif()
+
+# --- kanban_cpp (lives in apps/, issue 0096) ---
+set(_KANBAN_CPP_DIR ${CMAKE_SOURCE_DIR}/../apps/kanban_cpp)
+if(EXISTS ${_KANBAN_CPP_DIR}/CMakeLists.txt)
+    add_subdirectory(${_KANBAN_CPP_DIR} ${CMAKE_BINARY_DIR}/apps/kanban_cpp)
+endif()