The XT32 decoder, in dual return mode, employs a check whether the
two returned points are identical. The way the point for comparison was
indexed was erroneous and ended up always being the 1st or 2nd block of
the packet, although there are a total of 8 blocks.

This field was missing earlier, leading to avoidable troubleshooting.

The XT32 decoder did not classify First+Last, First+Strongest as dual
return in its check.

Added the return mode constants to the header and to the check

The Pandar40P decoder decoded points in firing time order. Since all
other sensors use logical ordering (by ascending index), Pandar40P is
adapted to this convention.

LASER_RETURN_DISTANCE was defined as float, is now double. This brings
Pandar40P distance accuracy up to the level of all other sensors,
which calculate distance on the fly in higher precision.

Other sensors output in `return_group > channel > block` order, the XT32M
decoder was outputting `block > channel`.

The XT32M scan completion check involved timing checks. These are
currently unused and complicate the code.
Further, they prevent a generic implementation.
Thus, the check has been streamlined.

Fixes tier4#49, fixes tier4#48.

Multiple decoders (QT64, QT128, 64, XT32, 128) had distance checks using
comparison operators different to the other sensors
(e.g. `>` instead of `>=`).

Pandar40P had no min_range / max_range checks.

AT128, XT32, XT32M had no dual_return_threshold checks.

Identical points were not removed when
dual_return_distance_threshold = 0.

All of these checks are corrected/added with this commit.

The sin/cos azimuth lookup tables did not include the channel-wise
azimuth offset in their calculation, leading to up to 0.166 deg of
azimuth error in the output X/Y values.

The tables have been replaced with sinf/cosf calls.

Unit tests for Hesai decoders were not setting
`dual_return_distance_threshold` at all, causing it to be `0`
implicitly. This caused a large number of duplicate points to be
output by the decoders.

The distance is set to `0.1 [m]` for all Hesai sensors now, which is the
default in the Hesai launch file.