Show rsync verbose output in TUI and application log

Replace tee with _snaplog_tee shell function that writes each line
unbuffered to three destinations: snapshot log, application log file,
and stderr (which the TUI captures for live display). This fixes the
issue where rsync file-by-file output was invisible in both the Logs
screen and the Running Tasks view due to pipe buffering.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

lib/rclone.sh

@@ -98,7 +98,7 @@ _rclone_cmd() {
     local rc=0
     if [[ -n "${_TRANSFER_LOG:-}" && "$subcmd" == "copy" ]]; then
         echo "=== rclone copy $* ===" >> "$_TRANSFER_LOG"
-        rclone "$subcmd" "${rclone_opts[@]}" --verbose "$@" > >(tee -a "$_TRANSFER_LOG") 2>&1 || rc=$?
+        rclone "$subcmd" "${rclone_opts[@]}" --verbose "$@" > >(_snaplog_tee) 2>&1 || rc=$?
     else
         rclone "$subcmd" "${rclone_opts[@]}" "$@" || rc=$?
     fi

lib/snaplog.sh

@@ -4,6 +4,16 @@
 [[ -n "${_GNIZA4LINUX_SNAPLOG_LOADED:-}" ]] && return 0
 _GNIZA4LINUX_SNAPLOG_LOADED=1
 
+# Tee helper: writes each line to the transfer log, app log, and stderr (TUI).
+# Used as process substitution target: cmd > >(_snaplog_tee) 2>&1
+_snaplog_tee() {
+    while IFS= read -r line; do
+        echo "$line" >> "${_TRANSFER_LOG}"
+        [[ -n "${LOG_FILE:-}" ]] && echo "$line" >> "${LOG_FILE}"
+        echo "$line" >&2
+    done
+}
+
 # Initialize snapshot log directory and transfer log file.
 snaplog_init() {
     _SNAP_LOG_DIR=$(mktemp -d "${WORK_DIR}/gniza-snaplog-XXXXXX")

lib/transfer.sh

@@ -57,7 +57,7 @@ rsync_to_remote() {
         local rc=0
         if [[ -n "${_TRANSFER_LOG:-}" ]]; then
             echo "=== rsync: $source_dir -> ${REMOTE_USER}@${REMOTE_HOST}:${remote_dest} ===" >> "$_TRANSFER_LOG"
-            "${rsync_cmd[@]}" > >(tee -a "$_TRANSFER_LOG") 2>&1 || rc=$?
+            "${rsync_cmd[@]}" > >(_snaplog_tee) 2>&1 || rc=$?
         else
             "${rsync_cmd[@]}" || rc=$?
         fi
@@ -133,7 +133,7 @@ rsync_local() {
         local rc=0
         if [[ -n "${_TRANSFER_LOG:-}" ]]; then
             echo "=== rsync (local): $source_dir -> $local_dest ===" >> "$_TRANSFER_LOG"
-            rsync "${rsync_opts[@]}" "$source_dir" "$local_dest" > >(tee -a "$_TRANSFER_LOG") 2>&1 || rc=$?
+            rsync "${rsync_opts[@]}" "$source_dir" "$local_dest" > >(_snaplog_tee) 2>&1 || rc=$?
         else
             rsync "${rsync_opts[@]}" "$source_dir" "$local_dest" || rc=$?
         fi