Prepare Rec v35r7

See merge request !3384

Fix extrapolation to beamspot when calculating track ClosestToBeam states

See merge request !3383

Updates to FTTrackMonitor (new plots, bugfixes)

See merge request !3373

Towards dropping GaudiAlgorithm, round 2

See merge request !3381

bug fix: fix typo introduced !3378

See merge request !3379

Cleanup FunctorCore

See merge request !3378

- `struct` doesn't `public` declaration
- prefer `mag` over `sqrt(mag2)`
- avoid special handling of `SmartRef` -- instead, use the fact that it has
  pointer semantics
- add constraints to some template functions, and prefer this to checking
  for explicit 'is_legacy_particle`
- use already existing `always_false` instead of introducing
  `assert_error` which does the same (and which has a name that doesn't
  match what it really does, but is named after what it could be used
  for)
- fix spelling
- remove redundant `deref_if_ptr`
- move 'internal' python functors (i.e. those whose name starts with
  `_`) into the scope of the functor that uses them instead of leaving
  them at global scope

Towards dropping GaudiAlgorithm

See merge request !3369

More detailed parameterised scattering for no UT scenario

Closes #379

See merge request !3310

Add MCPrimaries and more MC functors

See merge request !3279

Fix muon functor documentation

See merge request !3367

FT fix clusters per beam beam bunch crossing histogram

See merge request !3365

Move {FTNZS,IMuonTrack} to use RawBank::View as input instead of RawEvent

See merge request !3364

Cleaned up forgotten .gitignore file when dir was dropped

See merge request !3366

- clean up header file setup in MuonMatch

Added functional flavour taggers

See merge request !3160