All proc macros (`pack!`, `dispatcher!`, `#[chain]`, `#[program_setup]`,
`#[dispatcher_clap]`, `#[derive(Groupped)]`) now parse program names as
`syn::Path` instead of bare `Ident`, allowing use of paths like
`crate::MyProgram` or `my_crate::MyProgram`.

The default program name `ThisProgram` is no longer re-exported or
required
as an import — generated code references `crate::ThisProgram` directly.