fix(lotw): decouple QSO records from certificate station; skip un-signable records

- Remove LOCATION_MISMATCH check: the recorded myGrid never enters the
  TQ8 (the tSTATION grid is signed from the current certificate station),
  so a portable/ADIF-imported record with a different grid must not block
  upload. Logging and uploading are now fully decoupled from the
  certificate location.
- Fingerprint now covers the CONTACT only (call, date, band, mode,
  satellite, freq), excluding station fields: changing grid/zones/county/
  IOTA no longer invalidates ledger entries, so already-uploaded contacts
  are not re-queued and rejected as duplicates.
- prepare(): catch un-signable contacts per-record instead of aborting
  the whole batch; count them as skipped and upload the rest.
- audit(): count lotwUploaded records as uploaded (ledger-loss fallback).

core/data/src/main/java/com/rtbishop/look4sat/core/data/lotw/LoTWSigner.kt

@@ -24,14 +24,6 @@ internal class LoTWSigner(private val config: LoTWConfig) {
         if (date < key.info.firstQsoDate || (key.info.lastQsoDate.isNotBlank() && date > key.info.lastQsoDate) || record.startUtcMillis > now) {
             fail(LoTWProblem.QSO_DATE, call)
         }
-        val grids = buildList {
-            addAll(station.getValue("GRIDSQUARE").split(',').map(String::trim))
-            station["MY_VUCC_GRIDS"]?.split(',')?.map(String::trim)?.let(::addAll)
-        }.filter(String::isNotBlank)
-        if (record.myGrid.isNotBlank() && grids.none { grid ->
-            val local = record.myGrid.trim().uppercase(Locale.US)
-            grid.startsWith(local) || local.startsWith(grid)
-        }) fail(LoTWProblem.LOCATION_MISMATCH, call)
         fun mhz(hz: Long?): String = hz?.let { BigDecimal.valueOf(it, 6).stripTrailingZeros().toPlainString() }.orEmpty()
         val fields = linkedMapOf(
             "BAND" to config.band(record.band, record.txFrequencyHz, true),
@@ -46,8 +38,12 @@ internal class LoTWSigner(private val config: LoTWConfig) {
             "SAT_NAME" to if (record.isSatellite) config.satellite(record.satelliteName, date) else ""
         ).filterValues { it.isNotBlank() }
         val signData = (config.stationOrder.map { station[it].orEmpty() } + config.contactOrder.map { fields[it].orEmpty() }).joinToString("")
+        // Fingerprint identifies the CONTACT only (call, date/time, band, mode,
+        // satellite, frequency). Station fields (grid, zones, county, IOTA) are
+        // deliberately excluded: changing the station location must not change
+        // the fingerprint, otherwise previously-uploaded contacts would lose
+        // their ledger entry and be re-uploaded (and rejected as duplicates).
         val identity = field("CALL", key.info.callsign) + field("DXCC", key.info.dxcc.toString()) +
-            station.toSortedMap().entries.joinToString("") { field(it.key, it.value) } +
             fields.entries.joinToString("") { field(it.key, it.value) }
         val hash = MessageDigest.getInstance("SHA-256").digest(identity.toByteArray(Charsets.UTF_8)).joinToString("") { "%02x".format(it) }
         return LoTWContact(record, fields, signData, hash)

core/data/src/main/java/com/rtbishop/look4sat/core/data/lotw/LoTWUploadRepository.kt

@@ -167,7 +167,7 @@ class LoTWUploadRepository internal constructor(
                 coroutineContext.ensureActive()
                 when {
                     record.status != QsoStatus.COMPLETE -> unavailable++
-                    record.lotwReceived -> uploaded++
+                    record.lotwReceived || record.lotwUploaded -> uploaded++
                     else -> {
                         val contact = try {
                             signing.signer.contact(record, signing.key, signing.location, now())
@@ -199,8 +199,15 @@ class LoTWUploadRepository internal constructor(
             val unique = hashSetOf<String>()
             val contacts = records.sortedBy { it.startUtcMillis }.mapNotNull { record ->
                 coroutineContext.ensureActive()
-                if (record.status != QsoStatus.COMPLETE || (record.lotwReceived && !resubmit)) { skipped++; return@mapNotNull null }
-                val contact = signing.signer.contact(record, signing.key, signing.location, now())
+                if (record.status != QsoStatus.COMPLETE || ((record.lotwReceived || record.lotwUploaded) && !resubmit)) { skipped++; return@mapNotNull null }
+                val contact = try {
+                    signing.signer.contact(record, signing.key, signing.location, now())
+                } catch (_: LoTWOperationException) {
+                    // One un-signable record must not abort the whole batch:
+                    // skip it, count it, and let the rest upload.
+                    skipped++
+                    return@mapNotNull null
+                }
                 val previous = ledger[contact.fingerprint]
                 when {
                     (previous == "accepted" && !resubmit) || !unique.add(contact.fingerprint) -> { skipped++; null }