refactor: Replace Path 1/Path 2 terminology with typed edge vocabulary (#44)

Replace ambiguous "Path 1" and "Path 2" terminology with precise typed edge
vocabulary throughout tutorial documentation:

- Path 1 → "Direct Location (EVENT_SAMPLE_LOCATION)"
- Path 2 → "Site-Mediated Location (EVENT_SAMPLING_SITE → SITE_LOCATION)"

Add documentation of the 14 iSamples typed edge types which provide
unambiguous vocabulary for describing relationships:
- MSR_PRODUCED_BY, EVENT_SAMPLE_LOCATION, EVENT_SAMPLING_SITE, SITE_LOCATION, etc.

Updated files:
- parquet_cesium.qmd: Full documentation section rewrite, code comments, UI text
- parquet_cesium_wide.qmd: Same refactoring with wide format column mappings
- oc_parquet_enhanced.qmd: 2 Path references updated

This change improves documentation precision and aligns with Eric's canonical
query formulation which requires both direct location AND site provenance.

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

Co-authored-by: Claude <[email protected]>

Author: rdhyee

tutorials/oc_parquet_enhanced.qmd

@@ -190,16 +190,16 @@ viewof relationshipTable = Inputs.table(relationshipPatterns, {
 ❌ **Common Mistake**: Assuming direct Sample → Location relationships
 ✅ **Reality**: All location queries require multi-hop traversal through SamplingEvent
 
-### The Correct Paths Discovered
+### The Correct Traversals Discovered (Using Typed Edges)
 
-**Path 1: Direct Event Location**
+**Direct Location (via EVENT_SAMPLE_LOCATION)**
 ```
-MaterialSampleRecord → produced_by → SamplingEvent → sample_location → GeospatialCoordLocation
+MaterialSampleRecord → MSR_PRODUCED_BY → SamplingEvent → EVENT_SAMPLE_LOCATION → GeospatialCoordLocation
 ```
 
-**Path 2: Via Site Location**
+**Site-Mediated Location (via EVENT_SAMPLING_SITE → SITE_LOCATION)**
 ```
-MaterialSampleRecord → produced_by → SamplingEvent → sampling_site → SamplingSite → site_location → GeospatialCoordLocation
+MaterialSampleRecord → MSR_PRODUCED_BY → SamplingEvent → EVENT_SAMPLING_SITE → SamplingSite → SITE_LOCATION → GeospatialCoordLocation
 ```
 
 This discovery unlocked **1,096,274 samples** that were previously inaccessible due to incorrect query patterns!