Add support field to router marker preset

[kjonosm]

Description, Motivation & Context

Common combination

Related issues

Closes #1527

Links and data

Relevant OSM Wiki links:
https://wiki.openstreetmap.org/wiki/Tag:information%3Droute_marker
https://wiki.openstreetmap.org/wiki/Key:support

Relevant tag usage stats:

https://taginfo.openstreetmap.org/tags/information=route_marker#combinations

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## Test-Documentation

### Preview links & Sidebar Screenshots

<!-- Use the preview to find examples, select the feature in question and **copy this link here**.
     Find examples of nodes/areas. Find examples with a lot of tags or very few tags. – Whatever helps to test this thoroughly.
     Add relevant **screenshots** of the sidebar of those examples. -->

<!-- FYI: What we will check:
     - Is the [icon](https://github.com/ideditor/schema-builder/blob/main/ICONS.md) well chosen.
     - Are the fields well-structured and have good labels.
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### Search

<!-- **Test the search** of your preset and share relevant **screenshots** here.
     - Test the preset name as search terms.
     - Also test the preset terms and aliases as search terms (if present). -->

### Info-`i`

<!-- **Test the info-i** for your fields and preset and share relevant **screenshots** here.
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     [Learn more…](https://github.com/openstreetmap/id-tagging-schema/blob/main/CONTRIBUTING.md#info-i)
 -->

### Wording

- [ ] American English
- [ ] `name`, `aliases` (if present) use Title Case
- [ ] `terms` (if present) use lower case, sorted A-Z
<!-- Learn more in https://github.com/openstreetmap/id-tagging-schema/blob/main/GUIDELINES.md#2-design-the-preset -->

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[kjonosm]

[tyrasd]

(moved it to the moreFields section)