Resolves DSL path values to absolute filesystem paths at runtime.

Why

Mix releases relocate priv/ files: in dev they live at <project>/priv/...; in a release at <release>/lib/<app>-<version>/priv/.... A literal relative string baked into a Spark DSL at compile time only works in dev.

Mirroring the idiomatic Plug.Static pattern (from: {:my_app, "priv/static"}), AshTypst accepts either:

• a String.t() — used verbatim (caller's responsibility to provide a path that resolves correctly in every environment), or
• a {atom(), String.t()} tuple — resolved at runtime via Application.app_dir/2, which returns the correct absolute path in dev, test, and Mix releases.

Examples

iex> AshTypst.PathResolver.resolve("priv/typst")
"priv/typst"

iex> path = AshTypst.PathResolver.resolve({:ash_typst, "priv/typst"})
iex> String.ends_with?(path, "ash_typst/priv/typst")
true