chore(release): train-v0.3.0

Build 3.

Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

apps/train/halkyon_train_flutter/assets/whats_new/0.3.0.en.txt

@@ -0,0 +1,7 @@
+- Your weight, entered on Progress or read from Health Connect, in kilograms or pounds.
+- A workout's page redone: readable maps in the app's language, and routes open near you.
+- A day's page of its own, in cards, with its night and Recharge.
+- Hold a chart to read the value under your finger.
+- Where sync stands in Settings, with Sync now.
+- A question mark beside a setting explains it.
+- An authenticator's key can be copied, and its codes have six digits.