Traffic signs: build script, POI picker, map overlay

[tordans]

Problem (user story)

As an OpenStreetMap mapper surveying roads in Germany, I want to add and review traffic_sign tags without memorizing StVO codes or the exact DE: / ; / , composition rules, so that I can tag signs accurately and see them on the map while editing.

Acceptance criteria

• When the map country has a traffic-sign catalog (initially DE), POI fields traffic_sign, traffic_sign:forward, and traffic_sign:backward show a + control that opens a searchable sign picker.
• The picker supports multi-select, frequently-used defaults on empty search, compose on apply, and decompose on open while preserving unrecognized fragments as “other” chips.
• A display setting Show Traffic Signs draws compact sign chains on nodes and ways (with directional tag handling).
• A prep script (src/traffic-signs/update.sh) bundles index metadata and SVG assets from @osm-traffic-signs/converter, wired into src/update_all.sh.

Implementation notes (by Cursor)

Build pipeline (src/traffic-signs/)

• update.sh / build_index.mjs: runs npm install and consumes @osm-traffic-signs/converter to emit:
  • TrafficSignIndex.json — per-country entries, search tokens, redirect map, frequently-used list, named values
  • TrafficSigns.xcassets — 202 DE SVG imagesets (vector-preserving)
• Hooked into src/update_all.sh alongside presets and POI icons.

Runtime (Swift)

• TrafficSignCatalog / TrafficSignComposer: load bundled index; offline compose/decompose aligned with package rules (DE: prefix, ; between signs, , within compound signs, redirects, named values).
• TrafficSignPickerViewController: search field, horizontal selected chips (catalog thumbnails + “other”), 4-column results grid; applies composed tag value.
• PresetValueTextField: + button (contactAdd) for traffic_sign* keys when currentRegion.country has a catalog.
• TrafficSignOverlayLayer: bead-chain icon overlay on visible nodes/ways; respects directional tags and generic fallback rules; gated by country catalog and user pref.
• Display settings: new Show Traffic Signs switch in Overlays section; UserPrefs.mapViewEnableTrafficSigns.

Scope / follow-ups

• Catalog is Germany-only today; additional countries can be added when they land in the npm package.
• Overlay refresh is tied to viewport changes; editor tag edits may need a pan/zoom nudge until map-data change subscription is added.
• Compose/decompose Swift port should stay in sync when bumping @osm-traffic-signs/converter — re-run src/traffic-signs/update.sh after upgrades.

Testing notes (by @tordans)

Please verify on a DE map extent (country detection → currentRegion.country == "de"):

POI picker

1. Select a node/way and open tags for traffic_sign (and :forward / :backward if preset exposes them).
2. Confirm + appears in DE, hidden outside catalog countries.
3. Tap + → picker opens with existing value decomposed into chips.
4. Empty search → frequently used signs (not an empty grid).
5. Search e.g. 205, 310, city_limit → grid updates.
6. Add/remove signs; tap Done → tag value updates with correct DE: / separators.
7. Edit a value containing free text or unknown parts → “other” chips remain after apply/reopen.

Map overlay

1. Display → Overlays → enable Show Traffic Signs.
2. Nodes with traffic_sign=* show icon chain at the point.
3. Ways with sign tags show chain along the way; check traffic_sign:forward / :backward and generic fallback cases.
4. Toggle off → overlays disappear. Outside DE → no overlay icons.

Build / release

1. cd src/traffic-signs && ./update.sh (requires Node/npm).
2. Full prep: cd src && ./update_all.sh includes traffic-signs step.
3. Xcode build on device/simulator; confirm assets and TrafficSignIndex.json are in the app bundle.

Regression

• Other POI field accessories (direction, opening hours, units) still work.
• Data overlay / GPX / notes toggles unchanged.