chore: update lance dependency to v6.0.0-beta.7 (#3334)

## Summary
- Update Lance Rust dependencies to `6.0.0-beta.7` using
`ci/set_lance_version.py`.
- Update Java `lance-core.version` to `6.0.0-beta.7`.
- Align Arrow/DataFusion/PyO3 dependency versions and apply required
compatibility fixes for the Lance upgrade.

Triggering tag:
[v6.0.0-beta.7](https://github.com/lance-format/lance/releases/tag/v6.0.0-beta.7)

## Verification
- `cargo clippy --workspace --tests --all-features -- -D warnings`
- `cargo fmt --all`

python/src/expr.rs

@@ -17,7 +17,7 @@ use pyo3::{Bound, PyAny, PyResult, exceptions::PyValueError, prelude::*, pyfunct
 /// [`expr_lit`] and combined with the methods on this struct.  On the Python
 /// side a thin wrapper class (`lancedb.expr.Expr`) delegates to these methods
 /// and adds Python operator overloads.
-#[pyclass(name = "PyExpr")]
+#[pyclass(name = "PyExpr", from_py_object)]
 #[derive(Clone)]
 pub struct PyExpr(pub DfExpr);