– before erroring out, check whether the residuals for the block are already
  zero (in which case, move to next block)
– improve error message that is printed otherwise

Note that trying to solve under-determined blocks (as in dynare_solve.m) would
require too many changes in the existing code, so let’s leave it out.

Closes: #1851

– Bugfix with temporary terms in block+bytecode
– Block decomposition: (likely) performance improvement in static file in
  relation to temp terms
– Code factorization

The configuration is still unsatisfactory for quite a few items.

[skip ci]

– bugfixes in JSON output
– various refactorings

Fix typo in Ramsey_steady_file.mod

See merge request !2052

– Fix interaction of temporary terms with steady_state operator.
  Incidentally, this implies that external functions can no longer be used inside
  steady_state operators.
– JSON output: remove duplicate “rhs” field when RHS of equation is non-zero
  constant
– Bytecode: remove hack for exogenous deterministic index

Ref. !2051

Ref. !2049

Except for libdynare++, since Dynare++ is not ready (and is probably not worth
fixing by adding [[maybe_unused]] tags).

– dyn_forecast: remove unused output argument
– Various refactorings

Ref. !2048

Ref. !2047

Ref. !2046

Related to #1851

By the way, remove other unnecessary calls to that constructor.

in model inversion routines.

Introduced in patch 8b197bf7 which incidentally reduced the precision to six digits.