Bug: marti_archive: false is silently dropped by from_geojson()

[chriselsen]

Summary

from_geojson() cannot produce a CoT with an explicit <marti archive="false">. The property that
controls it, feature.properties.marti_archive, is read with truthy checks in three places instead of
!== undefined, so false is indistinguishable from "not set" and the attribute is silently omitted.

// lib/parser/from_geojson.ts:103-113
if (feature.properties.dest || feature.properties.marti_archive) {
    cot.event.detail.marti = {};

    if (feature.properties.marti_archive) {
        cot.event.detail.marti._attributes = { archive: true };
    }

    if (feature.properties.dest) {
        const dest = !Array.isArray(feature.properties.dest) ? [ feature.properties.dest ] : feature.properties.dest;
        cot.event.detail.marti.dest = dest.map((dest) => {
            return { _attributes: { ...dest } };
        });
    }
}

marti_archive: true works correctly. marti_archive: false produces byte-identical output to
marti_archive: undefined (no dest set): no <marti> element is emitted at all, so nothing about
archiving is asserted one way or the other on the wire.

Reproduction

import { from_geojson } from '@tak-ps/node-cot/lib/parser/from_geojson.js';

const cot = await from_geojson({
    type: 'Feature',
    properties: { marti_archive: false },
    geometry: { type: 'Point', coordinates: [0, 0] },
});

console.log(cot.raw.event.detail.marti); // undefined - expected { _attributes: { archive: false } }

Why this matters

archive on <marti> is not cosmetic. On TAK Server, SubmissionService reads it per-message
(String archive = ((Element) marti).attributeValue("archive")) and sets a context flag that
RepositoryService checks before writing the message to the retention database. The message-level tag
takes precedence over the receiving input's own archive default — it's read by a listener added after
the input-level one, so it always overwrites. That means a client is fully able to say "don't retain this
specific CoT" independent of how the input is configured, provided it can actually put archive="false"
on the wire — which from_geojson() currently prevents.

Concretely: a consumer wants to mark certain generated CoTs as non-archival on an input whose default is
archive="true". There is no way to express that through this library. Every marti_archive value except
true produces the same (archived) result.

Fix

Two small changes, both backward compatible — true and undefined behave identically to today; only
false changes, from a no-op to doing what it already claims to do:

-    if (feature.properties.dest || feature.properties.marti_archive) {
+    if (feature.properties.dest || feature.properties.marti_archive !== undefined) {
         cot.event.detail.marti = {};

-        if (feature.properties.marti_archive) {
-            cot.event.detail.marti._attributes = { archive: true };
+        if (feature.properties.marti_archive !== undefined) {
+            cot.event.detail.marti._attributes = { archive: feature.properties.marti_archive };
         }

The outer gate needs to widen too — otherwise marti_archive: false with no dest still fails to create
the <marti> element at all, since the || never becomes true.

I verified the underlying XML serialization has no issue with a false attribute value —
@tak-ps/xml-js produces <marti archive="false"/> correctly; the bug is purely in the truthy checks
above, not downstream.