script executable

`arg-picker` is excluded from the workspace test command and tested
on its own due to conflicting `mingling_support` feature doctests.
Also remove unused `mling/res` ignore directories.

Use `--workspace` for build, clippy, and test tasks to cover
feature-gated code instead of relying on default features. Skip
workspace members in individual crate tasks to avoid redundant runs.

Add the Arborium JS library header to the documentation build via
RUSTDOCFLAGS and docs.rs metadata so generated docs include the
interactive Arborium components.

Add module-level docs for the build module via include_str and
restrict public re-exports to explicit items instead of glob imports.

Replace the old path-to-version patching with full workspace inheritance
resolution.  Each member's Cargo.toml now has all `workspace = true`
references inlined from `[workspace.package]` and
`[workspace.dependencies]`,
and the root Cargo.toml is stripped of those workspace sections to
become a
pure virtual manifest.  Post-package extraction also adds a bare
`[workspace]` to each standalone crate so it remains a valid workspace
root.

Replace the `builds` feature with `build` across the crate, keeping
a backward-compatible alias for the old name.  Update all internal
visibility from `#[doc(hidden)] pub mod` to `pub(crate) mod` and
reorganize the `__private` module into a dedicated `private.rs`.