fix: disinto init: race condition in post-push empty check (#773)

Replace the single-shot Forgejo API emptiness check in push_to_forge()
with a retry loop (up to 5 attempts, 2s apart). Forgejo needs a brief
delay to index pushed refs, so the immediate check could see stale
metadata reporting empty=true even though the push succeeded.

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

bin/disinto

@@ -861,19 +861,29 @@ push_to_forge() {
     return 1
   fi
 
-  # Verify the repo is no longer empty
-  local repo_info
-  repo_info=$(curl -sf --max-time 10 \
-    -H "Authorization: token ${FORGE_TOKEN}" \
-    "${forge_url}/api/v1/repos/${repo_slug}" 2>/dev/null) || repo_info=""
-  if [ -n "$repo_info" ]; then
-    local is_empty
-    is_empty=$(printf '%s' "$repo_info" | jq -r '.empty // "unknown"')
-    if [ "$is_empty" = "true" ]; then
-      echo "Warning: Forgejo repo still reports empty after push" >&2
-      return 1
+  # Verify the repo is no longer empty (Forgejo may need a moment to index pushed refs)
+  local is_empty="true"
+  local verify_attempt
+  for verify_attempt in $(seq 1 5); do
+    local repo_info
+    repo_info=$(curl -sf --max-time 10 \
+      -H "Authorization: token ${FORGE_TOKEN}" \
+      "${forge_url}/api/v1/repos/${repo_slug}" 2>/dev/null) || repo_info=""
+    if [ -z "$repo_info" ]; then
+      break  # API unreachable, skip verification
     fi
-    echo "Verify:  repo is not empty (push confirmed)"
+    is_empty=$(printf '%s' "$repo_info" | jq -r '.empty // "unknown"')
+    if [ "$is_empty" != "true" ]; then
+      echo "Verify:  repo is not empty (push confirmed)"
+      break
+    fi
+    if [ "$verify_attempt" -lt 5 ]; then
+      sleep 2
+    fi
+  done
+  if [ "$is_empty" = "true" ]; then
+    echo "Warning: Forgejo repo still reports empty after push" >&2
+    return 1
   fi
 }