Shipped: SYSTEM Kind for Plot State Persistence

What We Built

Debrief plots now persist your working context. When you save a plot, your time window, map viewport, and selected features are stored as SYSTEM features. When you reopen, you’re exactly where you left off.

The implementation adds:

• SYSTEM value to the kind discriminator enum
• SystemStateProperties with variant discriminator (state_type)
• Three state variants: temporal, spatial, selection
• Reserved state.* ID pattern for O(1) lookup

How It Works

SYSTEM features use Point geometry with empty coordinates:

{
  "type": "Feature",
  "id": "state.temporal",
  "geometry": {
    "type": "Point",
    "coordinates": []
  },
  "properties": {
    "kind": "SYSTEM",
    "state_type": "temporal",
    "start_time": "2024-01-15T09:00:00Z",
    "end_time": "2024-01-15T17:30:00Z"
  }
}

The schema validates that SYSTEM features have Point geometry with empty coordinates and correctly-formatted IDs. Invalid structures are rejected at parse time, not runtime.

Evidence

All tests pass (53 total):

• 3 valid SYSTEM fixtures (temporal, spatial, selection)
• 2 invalid SYSTEM fixtures (geometry validation, ID pattern)
• Full round-trip validation in Python and TypeScript

Generated artifacts:

• Pydantic models with SystemState class
• TypeScript interfaces with full type safety
• JSON Schema for frontend validation

What’s Next

This enables the viewport save/restore feature in the loader app. With the schema in place, the next step is wiring up the UI to read/write these state features when plots are opened and saved.

→ View the PR