Fix intervalometer flickering: implement proper ramping + IDS SDK exposure query

- Fixed instant exposure jumps causing visible flickering
- Implemented proper gradual ramping using ramp_step variable
- Added IDS uEye SDK integration for accurate exposure range query
- Added hcam property to idsueyesrc to expose camera handle
- Updated intervalometer to query on first frame when camera is ready
- Added comprehensive debug documentation with tuning guide

For dawn/dusk time-lapse, use:
  ramp-rate=vslow update-interval=1000

gst/intervalometer/CMakeLists.txt

@@ -6,7 +6,8 @@ set (HEADERS
   gstintervalometer.h)
     
 include_directories (AFTER
-  ${ORC_INCLUDE_DIR})
+  ${ORC_INCLUDE_DIR}
+  ${IDSUEYE_INCLUDE_DIR})
 
 set (libname gstintervalometer)
 
@@ -20,7 +21,8 @@ target_link_libraries (${libname}
   ${GOBJECT_LIBRARIES}
   ${GSTREAMER_LIBRARY}
   ${GSTREAMER_BASE_LIBRARY}
-  ${GSTREAMER_VIDEO_LIBRARY})
+  ${GSTREAMER_VIDEO_LIBRARY}
+  ${IDSUEYE_LIBRARIES})
   
 if (WIN32)
   install (FILES $<TARGET_PDB_FILE:${libname}> DESTINATION ${PDB_INSTALL_DIR} COMPONENT pdb OPTIONAL)