Keep every package module under the PuduLangMcp root #5

Problem

pudu.toml declares the module root PuduLangMcp, but 0.1.0 ships its modules at the top level (App.*, Domain.*, Services.*, Utils.*, Constants.*, Errors.*, Generated.*). A consumer that installs @chrismichaelps/pudu-lang-mcp and has a module with one of those names, such as the App and Domain layers pudu init generates, stops compiling. With a consumer App/Context.pudu, the package's App/Completion.pudu fails with E3035 Context declares no type Context.

Acceptance

• Every module the package ships, other than the executable entry Main, is PuduLangMcp or under PuduLangMcp.*.
• A regression test fails when a source module leaves the root.
• The wiki mirror, tools, and README follow the new layout.
• A consumer with its own App.Context imports and serves the package.
• Released as 0.1.1.