format go code before generate it

fix doc

Support toml source

support xml source

Add prefix/suffix to struct name

1. normalize the struct and filed name
  - remove illegal char
  - if the name is empty, then use `A`
  - if the name start with a number, the prepend `N` to the name
2. Add prefix/suffix to the struct name
3. change codecov to version 4

update denpendencies

Support yml alias

Support input source: yaml

Exit -1 if error occures

If there are some errors, print the error message and the exit -1

Support null/nil/any Value

1. Parse json null value as Any type
2. Parse go  any value as Any type
3. Parse pb any value as Any type