fix: allow permutation reader to be used with remote tables (#3019)

There were two issues:

1. The python code needs to get access to the underlying rust table to
setup the permutation reader and the attributes involved in this differ
between the python local table and remote table objects.
~~2. The remote table was sending projection dictionaries as arrays of
tuples and (on LanceDB cloud at least) it does not appear this is how
rest servers are setup to receive them.~~ (this is now fixed as #3023)

~~Leaving as draft as this is built on
https://github.com/lancedb/lancedb/pull/3016~~

python/src/permutation.rs

@@ -239,6 +239,21 @@ impl PyPermutationReader {
             .collect::<PyResult<Vec<_>>>()?;
         Ok(Select::dynamic(&selection))
     }
+
+    fn table_from_py<'a>(table: Bound<'a, PyAny>) -> PyResult<Bound<'a, Table>> {
+        if table.hasattr("_inner")? {
+            Ok(table.getattr("_inner")?.downcast_into::<Table>()?)
+        } else if table.hasattr("_table")? {
+            Ok(table
+                .getattr("_table")?
+                .getattr("_inner")?
+                .downcast_into::<Table>()?)
+        } else {
+            Err(PyRuntimeError::new_err(
+                "Provided table does not appear to be a Table or RemoteTable instance",
+            ))
+        }
+    }
 }
 
 #[pymethods]
@@ -250,10 +265,8 @@ impl PyPermutationReader {
         permutation_table: Option<Bound<'py, PyAny>>,
         split: u64,
     ) -> PyResult<Bound<'py, PyAny>> {
-        let base_table = base_table.getattr("_inner")?.downcast_into::<Table>()?;
-        let permutation_table = permutation_table
-            .map(|p| PyResult::Ok(p.getattr("_inner")?.downcast_into::<Table>()?))
-            .transpose()?;
+        let base_table = Self::table_from_py(base_table)?;
+        let permutation_table = permutation_table.map(Self::table_from_py).transpose()?;
 
         let base_table = base_table.borrow().inner_ref()?.base_table().clone();
         let permutation_table = permutation_table