Add public building project setting

tests/project-state-snapshot.test.ts

@@ -18,6 +18,7 @@ function minimalSnapshot() {
       externalProjectNumber: null,
       buildingOwner: null,
       description: null,
+      isPublicBuilding: true,
       singlePhaseVoltageV: 230,
       threePhaseVoltageV: 400,
       enabledDistributionBoardSupplyTypes: [
@@ -142,7 +143,18 @@ describe("project state snapshot model", () => {
     );
   });
 
-  it("rejects pre-baseline snapshot shapes", () => {
+  it("upgrades the supported baseline snapshot with a safe building default", () => {
+    const baseline = structuredClone(minimalSnapshot());
+    baseline.schemaVersion = 1 as typeof baseline.schemaVersion;
+    delete (baseline.project as Record<string, unknown>).isPublicBuilding;
+
+    const upgraded = parseProjectStateSnapshot(baseline);
+
+    assert.equal(upgraded.schemaVersion, projectStateSnapshotSchemaVersion);
+    assert.equal(upgraded.project.isPublicBuilding, false);
+  });
+
+  it("rejects malformed baseline and unknown snapshot shapes", () => {
     const outdated = structuredClone(minimalSnapshot());
     delete (outdated.project as Record<string, unknown>).description;
     assert.throws(() => parseProjectStateSnapshot(outdated));