refactor(shell): Improve shell command naming and output formatting

- Renamed shell commands in  and  to be shorter
  and remove underscores (e.g.,  to ).
- Consolidated get functions into a single show command for both valve
  and Modbus settings (e.g., , ).
- Adjusted output formatting for show commands to be right-aligned and
  remove horizontal lines for better readability.
- Fixed missing getter function implementations in  and their
  declarations in .
- Ensured  is correctly selected in
  to make valve shell commands available.

software/Kconfig

@@ -1,2 +1,7 @@
 rsource "lib/Kconfig"
 rsource "lib/shell_valve/Kconfig"
+
+config SLAVE_NODE_APP
+	bool "Slave Node Application"
+	default y
+	select SHELL_VALVE