Feat: Implement Create operations with Select and omit - #11

1- define generateCUID/UUID() on the header template, and include other required imports

2- define dialect interface on the client, supporting Postgres and Sqlite dialects, detached from the dialect used in the migrations as the client will be standalone, should only embed the specified client thru template logic

3- define model input, select, and omit structs, allowing nested selects and omits for the relational fields, using the model's in relation select or omit struct

4- define createBuilder struct, which has generic methods to build the Select, omit, exec and handleInsert which is called by the create functions for all the models by passing generics instead of defining per model builder and bloating the client with too much structs

5- define the create function on the delegate struct, which transforms the recieved structs into raw sql accordingly, and excutes excuteInsert() which is a generic function with shared logic for creation and it's model-agnostic

6- write test cases for create operations