sync: drop non-finite replay gain values at the parse boundary

`toFloatOrNull` accepts `"Infinity"`, `"NaN"` and overflowing literals
like `"1e40"`, so a server (or a corrupt tag it read) could put a
non-finite gain or peak into the library. An infinite peak later caps the
applied gain at negative infinity, i.e. silence; an infinite gain clips
every sample to full scale.

Nothing consumes these columns yet, so this is only about not storing
values that cannot mean anything.

app/src/main/kotlin/com/subtracks/data/source/subsonic/SubsonicXml.kt

@@ -245,7 +245,7 @@ internal fun Attributes.attr(name: String): String = getValue(name) ?: ""
 
 internal fun Attributes.longAttr(name: String): Long? = attr(name).takeIf { it.isNotEmpty() }?.toLongOrNull()
 
-internal fun Attributes.floatAttr(name: String): Float? = attr(name).takeIf { it.isNotEmpty() }?.toFloatOrNull()
+internal fun Attributes.floatAttr(name: String): Float? = attr(name).takeIf { it.isNotEmpty() }?.toFloatOrNull()?.takeIf { it.isFinite() }
 
 internal fun Attributes.dateAttr(name: String): Long? = attr(name).takeIf { it.isNotEmpty() }?.let(IsoDate::parse)
 

app/src/test/kotlin/com/subtracks/data/source/subsonic/SubsonicXmlTest.kt

@@ -231,6 +231,33 @@ class SubsonicXmlTest {
         assertEquals(null, songs[1].albumPeak)
     }
 
+    @Test
+    fun ignoresNonFiniteReplayGainValues() {
+        val songs =
+            songs(
+                """
+                <subsonic-response status="ok">
+                  <searchResult3>
+                    <song id="s1" title="Junk">
+                      <replayGain trackGain="Infinity" albumGain="NaN" trackPeak="1e40" albumPeak="-Infinity"/>
+                    </song>
+                    <song id="s2" title="Mostly fine">
+                      <replayGain trackGain="-3.2" albumGain="NaN" trackPeak="0.98"/>
+                    </song>
+                  </searchResult3>
+                </subsonic-response>
+                """.trimIndent(),
+            )
+
+        assertEquals(null, songs[0].trackGain)
+        assertEquals(null, songs[0].albumGain)
+        assertEquals(null, songs[0].trackPeak)
+        assertEquals(null, songs[0].albumPeak)
+        assertEquals(-3.2f, songs[1].trackGain)
+        assertEquals(null, songs[1].albumGain)
+        assertEquals(0.98f, songs[1].trackPeak)
+    }
+
     @Test
     fun ignoresSongGenresThatAreNotDirectChildren() {
         val songs =