fix: Rework InterceptConfigsPreRunHandler to make sure configuration … (#7501)

* fix: Rework InterceptConfigsPreRunHandler to make sure configuration is pulled from all Viper sources

* docs: Add configuration documentation in a new file

server/doc.go

@@ -0,0 +1,27 @@
+/*
+The commands from the SDK are defined with `cobra` and configured with the
+`viper` package.
+
+This takes place in the `InterceptConfigsPreRunHandler` function.
+Since the `viper` package is used for configuration the precedence is dictated
+by that package. That is
+
+1. Command line switches
+2. Environment variables
+3. Files from configuration values
+4. Default values
+
+The global configuration instance exposed by the `viper` package is not
+used by Cosmos SDK in this function. A new instance of `viper.Viper` is created
+and the following is performed. The environmental variable prefix is set
+to the current program name. Environmental variables consider the underscore
+to be equivalent to the `.` or `-` character. This means that an configuration
+value called `rpc.laddr` would be read from an environmental variable called
+`MYTOOL_RPC_LADDR` if the current program name is `mytool`.
+
+Running the `InterceptConfigsPreRunHandler` also reads `app.toml`
+and `config.toml` from the home directory under the `config` directory.
+If `config.toml` or `app.toml` do not exist then those files are created
+and populated with default values.
+*/
+package server