Add wide format Cesium visualization tutorial

Complete 1:1 translation of parquet_cesium.qmd to wide format:
- All queries use p__* columns instead of edge row JOINs
- Eric's Query section translated to wide format
- Understanding Paths documentation with wide format references
- Helper functions for sample details, agents, keywords
- Geographic Location Classification section
- Updated sidebar navigation

Wide format advantages:
- 60% smaller file (275MB vs 691MB)
- 79% fewer rows (~2.5M vs ~11.6M)
- Simpler queries (3 JOINs vs 7+)
- 2-4x faster query performance

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: rdhyee

_quarto.yml

@@ -51,8 +51,10 @@ website:
           href: tutorials/parquet.qmd
         - text: "Zenodo iSamples OpenContext Tutorial"
           href: tutorials/zenodo_isamples_analysis.qmd
-        - text: "Cesium View"
+        - text: "Cesium View (Narrow)"
           href: tutorials/parquet_cesium.qmd
+        - text: "Cesium View (Wide)"
+          href: tutorials/parquet_cesium_wide.qmd
         - text: "Cesium View split sources"
           href: tutorials/parquet_cesium_split.qmd
         - text: "Narrow vs Wide Performance"