feat: improve fetch file output

- Updated the fetch file function in core_dl.sh and linuxgsm.sh to provide more informative output.
- Replaced the parentheses with square brackets to enclose the local filename.
- Added italics formatting to highlight the local filename.

lgsm/modules/core_dl.sh

@@ -403,7 +403,7 @@ fn_fetch_file() {
 				"${curlcmd[@]}" --progress-bar "${fileurl}" 2>&1
 				exitcode="$?"
 			else
-				echo -en "fetching ${fileurl_name} ${local_filename}...\c"
+				echo -en "fetching ${fileurl_name} [ ${italic}${local_filename}${default} ]\c"
 				"${curlcmd[@]}" --silent --show-error "${fileurl}" 2>&1
 				exitcode="$?"
 			fi

linuxgsm.sh

@@ -106,7 +106,7 @@ fn_bootstrap_fetch_file() {
 			trap fn_fetch_trap INT
 			# Larger files show a progress bar.
 
-			echo -en "fetching ${fileurl_name} ( ${local_filename} )\c"
+			echo -en "fetching ${fileurl_name} [ ${local_filename} ]\c"
 			curlcmd=$(curl --connect-timeout 10 -s --fail -L -o "${local_filedir}/${local_filename}" "${fileurl}" 2>&1)
 
 			local exitcode=$?