Move output tables above explanations for better UX (#39)

* Move output tables above explanations for better UX

Reorganized Cesium tutorial to show query results immediately after
clicking a point, before technical explanations.

Changes:
- Moved "Samples at Location" section (HTML table output) directly
  after "getGeoRecord (selected)" section
- "Understanding Paths in the iSamples Property Graph" now appears
  after results
- Removed duplicate output section from old location

Benefits:
- Users see results immediately without scrolling through explanations
- Technical details remain available below for those interested
- Cleaner, more intuitive information hierarchy

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

Co-Authored-By: Claude <noreply@anthropic.com>

* Add error handling for classification query failures

Wraps the color-coding classification query in try-catch to handle
intermittent DuckDB-WASM HTTP range request errors when querying
large remote parquet files.

Changes:
- Added try-catch around classification query execution
- Logs user-friendly error messages to console instead of crashing
- Page remains functional even if classification fails
- Provides helpful tips about retrying or using local cached file

Fixes occasional "Range request...offset is out of bounds" errors
that occur due to DuckDB-WASM limitations with remote files.

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

Co-Authored-By: Claude <noreply@anthropic.com>

* Suppress 'undefined' outputs from side-effect Observable cells

Added //| output: false directive to three Observable cells that
execute side effects but don't return values, which were displaying
"undefined" on the page.

Fixed cells:
- Camera initialization (PKAP view setup)
- Geocode search handler
- Classification button handler

These cells only perform side effects (camera control, event handling),
so their output should be suppressed.

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

Co-Authored-By: Claude <noreply@anthropic.com>

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Co-authored-by: Claude <noreply@anthropic.com>

Author: rdhyee