feat: return typed refresh job results (#4013)

## Problem

`refresh_column_async` returned a unit-result job even though durable
refresh jobs carry a canonical terminal result. Python callers could not
obtain row counts or source and published versions through the public
`Job` API, and local and remote refresh jobs exposed different result
semantics.

## Behavior

`refresh_column_async` now returns `Job[RefreshColumnResult]` for local
and remote tables. The general typed-job bridge binds each endpoint to
its public result model while preserving unit-result jobs and existing
status, wait, cancel, and timeout behavior. A local no-op refresh
reports no published version.

The Node.js API continues to resolve `wait()` as `void`; its binding
erases the Rust result type internally to preserve the existing public
contract.

## Ownership and integration boundary

LanceDB owns the language-neutral `Job<T>` contract and language-binding
decode. Sophon owns production and durable persistence of terminal
payloads. Sophon #7348 and #7378 now publish the canonical refresh
result for Function-backed and expression-backed refresh jobs,
respectively. The remote client fixture matches the merged server
schema; live deployment and end-to-end demo acceptance remain separate
rollout checks.

python/src/connection.rs

@@ -609,7 +609,7 @@ impl Connection {
                 .create_function_async(request)
                 .await
                 .infer_error()
-                .map(crate::job::FunctionJob::new)
+                .map(crate::job::Job::new_typed)
         })
     }
 

python/src/job.rs

@@ -5,72 +5,33 @@ use std::sync::Arc;
 
 use crate::runtime::future_into_py;
 use pyo3::{Bound, PyAny, PyRef, PyResult, pyclass, pymethods};
+use serde::Serialize;
 
 use crate::error::PythonErrorExt;
 
 #[pyclass]
 pub struct Job {
-    inner: Arc<lancedb::Job>,
-}
-
-/// Python bridge for a typed remote Function registration job.
-///
-/// The public Python layer decodes the canonical JSON returned by `wait`
-/// into its immutable `FunctionVersion` model.
-#[pyclass]
-pub struct FunctionJob {
-    inner: Arc<lancedb::Job<lancedb::function::FunctionVersion>>,
-}
-
-impl FunctionJob {
-    pub(crate) fn new(inner: lancedb::Job<lancedb::function::FunctionVersion>) -> Self {
-        Self {
-            inner: Arc::new(inner),
-        }
-    }
+    inner: Arc<lancedb::Job<std::result::Result<Option<String>, String>>>,
 }
 
 impl Job {
     pub(crate) fn new(inner: lancedb::Job) -> Self {
         Self {
-            inner: Arc::new(inner),
+            inner: Arc::new(inner.map(|()| Ok(None))),
         }
     }
-}
 
-#[pymethods]
-impl FunctionJob {
-    #[getter]
-    pub fn id(&self) -> Option<String> {
-        self.inner.id().map(str::to_string)
-    }
-
-    pub fn status(self_: PyRef<'_, Self>) -> PyResult<Bound<'_, PyAny>> {
-        let inner = self_.inner.clone();
-        future_into_py(
-            self_.py(),
-            async move { inner.status().await.infer_error() },
-        )
-    }
-
-    pub fn wait(self_: PyRef<'_, Self>) -> PyResult<Bound<'_, PyAny>> {
-        let inner = self_.inner.clone();
-        future_into_py(self_.py(), async move {
-            inner
-                .wait()
-                .await
-                .infer_error()?
-                .to_canonical_json()
-                .infer_error()
-        })
-    }
-
-    pub fn cancel(self_: PyRef<'_, Self>) -> PyResult<Bound<'_, PyAny>> {
-        let inner = self_.inner.clone();
-        future_into_py(self_.py(), async move {
-            inner.cancel().await.infer_error()?;
-            Ok(())
-        })
+    pub(crate) fn new_typed<T>(inner: lancedb::Job<T>) -> Self
+    where
+        T: Clone + Serialize + Send + Sync + 'static,
+    {
+        Self {
+            inner: Arc::new(inner.map(|result| {
+                serde_json::to_string(&result)
+                    .map(Some)
+                    .map_err(|error| format!("failed to serialize typed job result: {error}"))
+            })),
+        }
     }
 }
 
@@ -92,8 +53,10 @@ impl Job {
     pub fn wait(self_: PyRef<'_, Self>) -> PyResult<Bound<'_, PyAny>> {
         let inner = self_.inner.clone();
         future_into_py(self_.py(), async move {
-            inner.wait().await.infer_error()?;
-            Ok(None::<()>)
+            let result = inner.wait().await.infer_error()?;
+            result
+                .map_err(|message| lancedb::Error::Runtime { message })
+                .infer_error()
         })
     }
 

python/src/lib.rs

@@ -47,7 +47,6 @@ pub fn _lancedb(_py: Python, m: &Bound<'_, PyModule>) -> PyResult<()> {
     m.add_class::<Session>()?;
     m.add_class::<Table>()?;
     m.add_class::<crate::job::Job>()?;
-    m.add_class::<crate::job::FunctionJob>()?;
     m.add_class::<crate::job::JobInfo>()?;
     m.add_class::<crate::job::JobDescription>()?;
     m.add_class::<crate::job::JobFailureInfo>()?;

python/src/table.rs

@@ -1619,7 +1619,7 @@ impl Table {
         let inner = self_.inner_ref()?.clone();
         future_into_py(self_.py(), async move {
             let job = inner.refresh_column_async(column).await.infer_error()?;
-            Ok(crate::job::Job::new(job))
+            Ok(crate::job::Job::new_typed(job))
         })
     }