Add copy-dmgs.sh to copy DMGs to ~/Downloads with date+letter suffix

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

copy-dmgs.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+set -e
+cd "$(dirname "$0")"
+
+DATE=$(date +%Y%m%d)
+DEST="$HOME/Downloads"
+
+next_letter() {
+    local prefix="$1"
+    local letter="a"
+    while [ -f "${prefix}${letter}.dmg" ]; do
+        letter=$(echo "$letter" | tr 'a-y' 'b-z')
+        if [ "$letter" = "z" ] && [ -f "${prefix}z.dmg" ]; then
+            echo "Error: ran out of letter indices for today" >&2
+            exit 1
+        fi
+    done
+    echo "$letter"
+}
+
+if [ -f "target/debug/bundle/osx/Galaxy.dmg" ]; then
+    LETTER=$(next_letter "$DEST/Galaxy-debug-${DATE}")
+    cp "target/debug/bundle/osx/Galaxy.dmg" "$DEST/Galaxy-debug-${DATE}${LETTER}.dmg"
+    echo "Copied: $DEST/Galaxy-debug-${DATE}${LETTER}.dmg"
+else
+    echo "Skipped: no debug DMG found"
+fi
+
+if [ -f "target/release/bundle/osx/Galaxy.dmg" ]; then
+    LETTER=$(next_letter "$DEST/Galaxy-release-${DATE}")
+    cp "target/release/bundle/osx/Galaxy.dmg" "$DEST/Galaxy-release-${DATE}${LETTER}.dmg"
+    echo "Copied: $DEST/Galaxy-release-${DATE}${LETTER}.dmg"
+else
+    echo "Skipped: no release DMG found"
+fi