FEST: in-repo flattener bundles slim.json; release builds auto-refresh when stale

Amends decision #8: the producer now lives in tools/fest_flatten.py
(stdlib Python, streaming iterparse over the 115 MB M30 XML) instead of
an out-of-repo server job. It pulls fest251.zip from dmp.no, flattens
8934 active human-use brand entries (name/strength/unit/form/ATC +
modal package size from pakningsinfo), and writes the asset checked in
at app/src/main/assets/fest/slim.json — so autocomplete works offline
out of the box. preReleaseBuild depends on refreshFestData: fast-exits
under 30 days, keeps the old file on download failure (offline release
builds never break). FestRepository: downloaded cache wins over the
bundled asset.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

app/build.gradle.kts

@@ -71,6 +71,24 @@ android {
     sourceSets.getByName("androidTest").assets.srcDir("$projectDir/schemas")
 }
 
+// Release builds refresh the bundled FEST dataset when it's >30 days old.
+// The script fast-exits when fresh and keeps the old file on download failure,
+// so offline/CI release builds never break on this.
+val refreshFestData by tasks.registering(Exec::class) {
+    group = "fest"
+    description = "Regenerate app/src/main/assets/fest/slim.json from DMP's M30 extract if stale"
+    workingDir = rootProject.projectDir
+    commandLine(
+        "python3", "tools/fest_flatten.py",
+        "--out", "app/src/main/assets/fest/slim.json",
+        "--max-age-days", "30",
+    )
+}
+
+tasks.matching { it.name == "preReleaseBuild" }.configureEach {
+    dependsOn(refreshFestData)
+}
+
 dependencies {
     implementation(libs.kotlinx.coroutines.android)
     implementation(libs.androidx.core.ktx)