Well Event: generate_schedule takes an Eclipse case object directly

Replace the integer eclipse_case_id parameter on
RimcWellEventTimeline_generateSchedule with a
caf::PdmPtrField<RimEclipseCase*>. The execute() method no longer needs
to walk the project tree and look up the case by ID — the gRPC layer
resolves the object pointer for us.

generate_schedule_text passes the Eclipse case object through to the
underlying generate_schedule call, matching how add_perf_event /
add_well_keyword_event already take a WellPath object rather than an
ID.

ApplicationLibCode/ProjectDataModelCommands/RimcWellEventTimeline.h

@@ -225,7 +225,7 @@ public:
     QString                                       classKeywordReturnedType() const override;
 
 private:
-    caf::PdmField<int>  m_eclipseCaseId;
-    caf::PdmField<bool> m_includeWelsegs;
-    caf::PdmField<bool> m_includeCompsegs;
+    caf::PdmPtrField<RimEclipseCase*> m_eclipseCase;
+    caf::PdmField<bool>               m_includeWelsegs;
+    caf::PdmField<bool>               m_includeCompsegs;
 };