feat: Add "now" string and update formatAgo function (#4183)

Signed-off-by: James Rich <2199651+jamesarich@users.noreply.github.com>

core/ui/src/main/kotlin/org/meshtastic/core/ui/util/FormatAgo.kt

@@ -17,16 +17,38 @@
 package org.meshtastic.core.ui.util
 
 import android.text.format.DateUtils
+import com.meshtastic.core.strings.getString
+import org.meshtastic.core.strings.Res
+import org.meshtastic.core.strings.now
+import java.lang.System.currentTimeMillis
+import kotlin.time.Duration.Companion.milliseconds
+import kotlin.time.Duration.Companion.minutes
+import kotlin.time.Duration.Companion.seconds
 
-@Suppress("MagicNumber")
-fun formatAgo(lastSeenUnix: Int, currentTimeMillis: Long = System.currentTimeMillis()): String {
-    val timeInMillis = lastSeenUnix * 1000L
+/**
+ * Formats a given Unix timestamp (in seconds) into a relative "time ago" string.
+ *
+ * For durations less than a minute, it returns "now". For longer durations, it uses Android's
+ * `DateUtils.getRelativeTimeSpanString` to generate a concise, localized, and abbreviated representation (e.g., "5m
+ * ago", "2h ago").
+ *
+ * @param lastSeenUnixSeconds The Unix timestamp in seconds to be formatted.
+ * @return A [String] representing the relative time that has passed.
+ */
+fun formatAgo(lastSeenUnixSeconds: Int): String {
+    val lastSeenDuration = lastSeenUnixSeconds.seconds
+    val currentDuration = currentTimeMillis().milliseconds
+    val diff = (currentDuration - lastSeenDuration).absoluteValue
 
-    return DateUtils.getRelativeTimeSpanString(
-        timeInMillis,
-        currentTimeMillis,
-        DateUtils.SECOND_IN_MILLIS,
-        DateUtils.FORMAT_ABBREV_RELATIVE,
-    )
-        .toString()
+    return if (diff < 1.minutes) {
+        getString(Res.string.now)
+    } else {
+        DateUtils.getRelativeTimeSpanString(
+            lastSeenDuration.inWholeMilliseconds,
+            currentDuration.inWholeMilliseconds,
+            DateUtils.MINUTE_IN_MILLIS,
+            DateUtils.FORMAT_ABBREV_RELATIVE,
+        )
+            .toString()
+    }
 }