fix(worldclock): keep the local row's day label and legacy city names

The local row prepends "Local time" to the offset and day, so on a
phone a one-line summary cut off the day ("Tomorrow"), the part that
matters most on a long trip. It now wraps to two lines. Only Etc/
offsets and bare abbreviations are named by their offset; a legacy
place id such as US/Pacific keeps its place name. The picker's home
selection now derives from the same settings subscription the tab
uses.

docs/ARCHITECTURE.md

@@ -2407,7 +2407,7 @@ differ from it, so with no stored home the rule is always null, and Settings ›
 Clock says so under the switch rather than hiding it. A device set by UTC
 offset rather than by city reports an id like `Etc/GMT-9`, whose last segment
 has its sign reversed, so that row is named by its real offset ("GMT+9")
-instead (`ZoneCatalog.isCityId`).
+instead (`ZoneCatalog.hasPlaceName`).
 
 The row is not stored. It is `WorldClockUiState.Loaded.local`, built per tick
 by the source from the same `zones.current()` read the face uses, so a