chore(env): update environment.yml accordingly

Author: zhan4329

environment.yml

@@ -86,7 +86,9 @@ dependencies:
       - tifffile
       - shapely==2.0.7  # To be consistent with requirement.txt
       - sag-py-execution-time-decorator @ git+https://github.com/SamhammerAG/sag_py_execution_time_decorator.git@976c9683d561aadc0166495117c42cc1762633d7
-      # SPAC package pinned to specific commit for template compatibility (dev branch as of 2025-10-15)
-      - spac @ git+https://github.com/FNLCR-DMAP/SCSAWorkflow.git@49a6479d3083070064a6218f34125b5e86ad8e46#egg=spac
+      # Added: packages for heatmap mode in scatterplot
       - colorcet
       - git+https://github.com/holoviz/datashader.git
+      # SPAC package pinned to specific commit for template compatibility (dev branch as of 2025-10-15)
+      - spac @ git+https://github.com/FNLCR-DMAP/SCSAWorkflow.git@c2a248826b91880c62308e85e60cae9361c275d0#egg=spac
+