show more relevant presets when switching preset of an object

[tyrasd]

When changing the preset of an existing object, the preset list currently contains a few of the recently used presets and a relatively long "default" list of presets which match the selected feature's geometry. Listing the completely context-less list of "defaults" is in general not very useful: it is pretty unlikely that one wants to change a building feature to something completely different like a park for example.¹ Usually one wants to change an object's preset to either refine it (choosing to a more specific sub-preset, e.g. from a Doctor to a General Practitioner), or update the map by choosing a closely related preset (e.g. when switching from a shop=shoes to shop=clothes if a POI changed in reality or the POI was previously mapped incorrectly).

In this PR, the suggestions are based on the object's previous preset:

• if it was part of a category, show that category again (e.g. editing a highway=primary will offer the "Major Roads" category)
• if a preset has sub-presets: offer up to 5 of these (e.g. barrier=kerb will offer presets like Raised Curb, Lowered Curb, etc.)
• show the "partent" i.e. more generic preset if there is a matching one
• show up to 5 "sibling" presets

(currently this also increases the number of shown previously used presets from 4 to 5, see #9545)

Some unfinished business:

• should these be sorted differently, e.g. before the previously used presets)?
• should there be a visual separation between these suggestions, the recents and the defaults?
• investigate if a better sorting of candidates could be done when many siblings exist (e.g. building=yes might more likely be changed to a common building type like building=house, compared to something rare like building=yurt for example)
• add mechanism to offer more related presets (and/or more recently used presets)
• add test cases

Footnotes

1. There is a little bit of merit to not completely omit showing these defaults, tough: It teaches the mapper that there are many very different thing one can map in OSM: e.g. from natural features, landuse and water features, to points of interest, etc. ↩