Shift to dune from ocamlbuild

[sidkshatriya]

• Simpler to understand, more declarative
• Probably better integration with ocaml-lsp-server and editors in general due to dune's capabilities
• Auto-generate an opam file for more explicit dependencies

Please test this locally and let me know whether you think this is a useful change

Notes

• Both native and byte code executables are produced at one go instead of explicitly needing to specify
• The executables can be found in src/<name-of-interpreter instead of the root directory

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The main reason for doing this personally is that I wanted better "code intelligence" in my editor which uses ocaml-lsp-server (which is the OCaml LSP server)