cli: smpy add <local path> for a workspace member writes a path source that uv rejects #442

What happened

In an smpy new workspace (members = ["host", "modules/*"]), after smpy create-module forest_plots --dest modules/forest_plots:

smpy add ../modules/forest_plots --path host --no-sync --yes
# -> simple_module_forest_plots = {path = "../modules/forest_plots", editable = true}
uv sync --all-packages
# error: `simple-module-forest-plots` is included as a workspace member, but references a path in `tool.uv.sources`.
#        Workspace members must be declared as workspace sources (e.g., `simple-module-forest-plots = { workspace = true }`).

Also: the dependency is added as >=0.1.0,<1.0 rather than unpinned like the scaffold's own sample module.

Expected

smpy add detects the path is inside the enclosing uv workspace's members and writes { workspace = true }. Ideally smpy create-module --dest modules/<name> inside a workspace offers to wire the host dependency itself, since that's the next step every time.

Minor

smpy add ./modules/forest_plots --path host resolves the path relative to --path, not the cwd, and the error ("host/modules/forest_plots has no entry point") doesn't mention that.