Xtrack

**Changes:**
- Fix in element insertion
- Update spacecharge examples and sps spacecharge test data.

**Full Changelog**: https://github.com/xsuite/xtrack/compare/v0.48.0...v0.48.1

**Changes:**
- New features in `Line.twiss`:
- Initial conditions can be provided at any point in the selected range.
- Initial conditions can be provided as keyword arguments, e.g. `line.twiss(ele_start='ip8', ele_stop='ip2', ele_init='ip1', betx=1., bety=2.)`.
- Twiss range can extend across the end of the line (useful to avoid unnecessary line cycle).
- `ele_co_search` can be provided to periodic twiss to perform the closed orbit search at a given point in the line (instead of start line). Useful to avoid failures when large orbit bumps extend across the start of the line.

**Changes:**
- Fix in skew quadrupole import from MAD-X.
- Rename `Line.vars.load_madx_optics_file` to `Line.vars.set_from_madx_file` (both are kept).

**Full Changelog**: https://github.com/xsuite/xtrack/compare/v0.47.1...v0.47.2

**Changes:**
- Fix: handle uninitialized variables in `load_madx_optics_file `

**Changes:**
- Introduce multi-turn closed solution search in twiss.
- Replace `particle_co_guess` with `co_guess` (can be also a dict).
- Fix for handling MAD-X expressions including arrows.

**Full Changelog**: https://github.com/xsuite/xtrack/compare/v0.46.5...v0.47.0

**Changes:**
- Add a workaround for issue with progress bar in notebooks.
- Fix issues with the default turn by turn monitor when tracking with the progress bar
- Fix issues with ele_start, ele_stop when tracking with the progress bar

**Full Changelog**: https://github.com/xsuite/xtrack/compare/v0.46.3...v0.46.5