docs: add gdb backtrace commands

- update CLN version
Signed-off-by: Lakshya Singh <lakshay.singh1108@gmail.com>

README.md

@@ -189,7 +189,7 @@ docker ps
 Getting logs from container
 ```bash
 # CONTAINER_NAME=lightningd-test
-docker container logs $CONTAINER_NAME
+docker container logs $CONTAINER_NAME > $CONTAINER_NAME.log
 ```
 
 Restarting containers
@@ -200,17 +200,32 @@ docker compose --profile vls stop
 docker compose --profile vls up
 ```
 
+Generating Backtrace from CLN core dump
+```bash
+# attach to the lightningd container
+docker container exec -u root -it lightningd-test sh
+
+# install gdb
+apk add gdb
+gdb /usr/libexec/c-lightning/plugins/pay /home/lightning/.lightning/testnet/core
+
+# get backtrace
+bt
+```
+
 Delete containers
 ```bash
 cd vls-container
 docker compose --profile vls down
 ```
 
+**NOTE**: If you want to start fresh make sure to delete the created docker volumes as well.
+
 ## Choosing Versions
 
 The currently set default versions for services is as follows in the [.env](.env) file:
 - **Bitcoin Core**: v26.0
-- **Core Lightning**: v24.02
+- **Core Lightning**: v24.02.2
 - **TXOO**: v0.6.4
 - **VLS**: v0.11.0