fix(roaming): drop auto GPS polling, show station position directly

Reverts the auto-update machinery after review — the page now simply mirrors the station position (站位) from the shared settingsRepo.stationPosition StateFlow, exactly what the Settings page shows:

- RoamingScreen: removed the LocationManager listeners, the 30s re-request loop, the provider filter and the location-disabled hint. No polling, no auto-updates; coordinates are whatever the station GPS says.
- Settings: removed the '漫游位置实时更新' toggle (stateOfRoamingLive, key, action, strings en/zh/tr) that caused the 'Other' card to overflow — the sixth unlabeled switch clipped past the card's rounded bottom edge was that row overflowing a fixed-height card. Card height back to 268.dp, five rows fit again.

Verified: core:domain tests, roaming/settings/app compile clean; zero references to RoamingLive remain.

core/data/src/main/java/com/rtbishop/look4sat/core/data/repository/SettingsRepo.kt

@@ -76,7 +76,6 @@ class SettingsRepo(
     private val keyStateOfUtc = "stateOfUtc"
     private val keyStateOfLightTheme = "stateOfLightTheme"
     private val keyStateOfNightMode = "stateOfNightMode"
-    private val keyStateOfRoamingLive = "stateOfRoamingLive"
     private val keyStationAltitude = "stationAltitude"
     private val keyStationLatitude = "stationLatitude"
     private val keyStationLongitude = "stationLongitude"
@@ -352,7 +351,6 @@ class SettingsRepo(
                 putBoolean(keyStateOfUtc, new.stateOfUtc)
                 putBoolean(keyStateOfLightTheme, new.stateOfLightTheme)
                 putBoolean(keyStateOfNightMode, new.stateOfNightMode)
-                putBoolean(keyStateOfRoamingLive, new.stateOfRoamingLive)
                 putBoolean(keyShouldSeeWarning, new.shouldSeeWarning)
                 putBoolean(keyShouldSeeWhatsNew, new.shouldSeeWhatsNew)
                 putString(keySstvMode, new.sstvMode)
@@ -370,7 +368,6 @@ class SettingsRepo(
         stateOfUtc = preferences.getBoolean(keyStateOfUtc, false),
         stateOfLightTheme = preferences.getBoolean(keyStateOfLightTheme, false),
         stateOfNightMode = preferences.getBoolean(keyStateOfNightMode, false),
-        stateOfRoamingLive = preferences.getBoolean(keyStateOfRoamingLive, true),
         shouldSeeWarning = preferences.getBoolean(keyShouldSeeWarning, true),
         shouldSeeWhatsNew = preferences.getBoolean(keyShouldSeeWhatsNew, true),
         sstvMode = preferences.getString(keySstvMode, null) ?: "Auto",