fix: make beacons session-only, slower and QSY-aware (#171)

Forgotten beacons kept filling the chat while nobody was at the station.

- The two enable switches are session state now: they start off, are
  never read from preferences.xml and are always stored as "false", so
  neither a stored switch nor an older release reading a newer file can
  start a beacon. The in-code default was "on" and started a beacon
  whenever the file was unreadable or had no <beaconCQ> block.
- The minimum interval rises from 1 to 5 minutes; the bundled template
  ships 10 instead of 1. Smaller stored values are raised when the
  timer is scheduled.
- BeaconFrequencyGuard switches a beacon off once a logger-reported
  transceiver frequency lies more than 2 kHz from the one reported when
  the beacon was switched on. UCXLog RadioInfo and Win-Test STATUS feed
  it wherever they already set MYQRG/SECONDQRG. Without SO2R the single
  radio stands for both categories, with SO2R each radio for its own.

Manual (DE/EN), changelog, website and PROJECT_CONTEXT updated.

Co-Authored-By: Claude <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NJ1tUJVmWChD9V5Pg7uH8X

app-desktop/src/main/i18n/strings_de.properties

@@ -473,7 +473,7 @@ profiles.changeAfterSwitch=Die Änderung wirkt erst nach einem erneuten Wechsel
 profiles.alreadyActive=Dieses Profil ist bereits aktiv.
 profiles.selectFirst=Zuerst ein Profil in der Tabelle wählen.
 beacon.invalidMessage=Der Bakentext ist ungültig: {0}
-beacon.intervalTooShort=Einen ganzzahligen Bakenabstand von mindestens {0} Minute eingeben.
+beacon.intervalTooShort=Einen ganzzahligen Bakenabstand von mindestens {0} Minuten eingeben.
 notification.invalidPort=„{0}" ist kein gültiger TCP-Port. Einen Wert von 1 bis 65535 eingeben.
 notification.invalidSpotter=„{0}" ist kein gültiges Spotter-Rufzeichen.
 notification.invalidCallsign=Bitte ein gültiges Rufzeichen eingeben.

app-desktop/src/main/i18n/strings_en.properties

@@ -482,7 +482,7 @@ profiles.changeAfterSwitch=The change takes effect after switching to this profi
 profiles.alreadyActive=This profile is already active.
 profiles.selectFirst=Select a profile in the table first.
 beacon.invalidMessage=The beacon message is invalid: {0}
-beacon.intervalTooShort=Enter a whole beacon interval of at least {0} minute.
+beacon.intervalTooShort=Enter a whole beacon interval of at least {0} minutes.
 notification.invalidPort="{0}" is not a valid TCP port. Enter a value from 1 to 65535.
 notification.invalidSpotter="{0}" is not a valid spotter callsign.
 notification.invalidCallsign=Please enter a valid callsign.

app-desktop/src/test/kotlin/kst4contest/view/compose/tabs/BeaconTabStateTest.kt

@@ -180,6 +180,20 @@ class BeaconTabStateTest(@TempDir private val tempDir: Path) {
             "restarting the timer per rejected keystroke would disturb the cooldown")
     }
 
+    /** Issue #171: one minute was allowed and was what the template shipped. */
+    @Test
+    fun `an interval below five minutes is refused and five is accepted`() {
+        val s = Session()
+        s.prefs.setBcn_beaconIntervalInMinutesMainCat(9)
+        val state = s.state()
+
+        assertNotNull(state.commitBeaconInterval("4"))
+        assertEquals(9, state.beaconIntervalMinutes)
+
+        assertNull(state.commitBeaconInterval("5"))
+        assertEquals(5, state.beaconIntervalMinutes)
+    }
+
     @Test
     fun `an interval that is not a whole number is refused`() {
         val s = Session()

app-desktop/src/test/kotlin/kst4contest/view/i18n/RemainingTextsFollowTheLanguageTest.kt

@@ -73,7 +73,7 @@ class RemainingTextsFollowTheLanguageTest {
 
             assertEquals("Wertung", score.title(), "the column title stayed in the old language")
             assertEquals(
-                "Einen ganzzahligen Bakenabstand von mindestens 1 Minute eingeben.",
+                "Einen ganzzahligen Bakenabstand von mindestens 5 Minuten eingeben.",
                 beacon.commitBeaconInterval("0"),
                 "the refusal from the tab state stayed in the old language",
             )