* configs form user crud

* configs form user crud

* code refactor

* code refactor

* configs for user variable update & add InitRSAConfig for alert.go

* configs for user variable update

* remove InitRSAConfig for alert.go

* add config of Center.Encryption

* migrate for config and set default value

* add annotation for Center.Encryption

* code refactor

* code refactor

* code refactor again

* code refactor

* remove userVariableCheck bool return

* remove userVariableCheck bool return

* optimize InitRSAConfig

* optimize InitRSAConfig

* optimize InitRSAConfig

* macro variable

* optimize config

* remove test function user-variable-ras

* code refactor config_cache

* code refactor again

* code refactor again

* ReplaceMacroVariables return string value & optimize code

* add user variable check on ckey, it is not recommended to use the period "."

* change configs ckey+external=uniqueness

* configs add add external value

* configs remove isInternal check(ckey is no longer unique field)

* update userVariableCheck

* migrate drop unique filed limit

* refactor rsa generate logic. read key pairs from config.toml(HTTP.RSA) if file is not exist generate rsa key paris and saving to database(configs).

* Improve the RSA key generation logic. In the first step, attempt to read key pairs from the database or the 'config.toml' file. If they don't exist, generate a new set of key pairs and store them in the database.

* optimize code

* ckey use C-style naming convention and optimize smtp validations

* change email logger. print host & port

* update init rsa config logically

* update migrate about DropUniqueFiled

* update migrate about DropUniqueFiled

* make migrating at the first step

* move config of rsa. generate in db.

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Co-authored-by: shardingHe <wangzihe@flashcat.cloud>
Co-authored-by: Yening Qin <710leo@gmail.com>