feat(map): VUCC default chip, own-grid bold at all zooms, roamed-grid blue stripes

- Grid mode now opens with the VUCC award chip selected by default (re-asserted
  on every grid-mode entry; the user's in-mode chip choice is preserved).
- The station's own grid outline is now drawn at every zoom level: 2-char field
  border below the sub-square zoom, 4-char square border above it (was hidden
  at the default entry zoom), stroke widened to 6f.
- Grids the account operated from (LoTW <MY_GRIDSQUARE>, satellite QSOs only)
  are covered with GridMaster-style blue 45° zebra stripes. The stripe paint is
  fully opaque so a worked+roamed cell shows pure-blue stripes with green
  between them — the two colors never alpha-blend into a teal/green mix.
- LoTW sync now parses and persists the roamed set (LoTWResult.Success +
  SettingsRepo key 'roamedGrids'), plumbed through MapState/MapViewModel into
  MaidenheadGridOverlay. Unit tests cover MY_GRIDSQUARE parsing (SAT-only,
  GRIDSQUARE non-leak, 4-char truncation).

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/ISettingsRepo.kt

@@ -102,6 +102,9 @@ interface ISettingsRepo {
     /** Confirmed satellite QSOs grouped by worked 4-char gridsquare (map tap detail). */
     fun getWorkedGridQsos(): Map<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>>
     fun setWorkedGridQsos(qsos: Map<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>>)
+    /** Distinct 4-char gridsquares the account operated from (LoTW <MY_GRIDSQUARE>). */
+    fun getRoamedGrids(): Set<String>
+    fun setRoamedGrids(grids: Set<String>)
     //endregion
 
     //region # LoTW confirmed-grids settings

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/LoTWResult.kt

@@ -23,7 +23,10 @@ sealed class LoTWResult {
     /** Report downloaded and parsed successfully. */
     data class Success(
         val grids: Set<String>,
-        val qsos: Map<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>>
+        val qsos: Map<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>>,
+        /** Distinct 4-char gridsquares the account itself operated from
+         *  (ADIF <MY_GRIDSQUARE>, satellite QSOs only) — "roamed/activated" grids. */
+        val roamedGrids: Set<String> = emptySet()
     ) : LoTWResult()
 
     /** HTTP 200 but LoTW replied with its login-error page (bad callsign/password). */