auto: increment master version to 15.0.74

fix(linux): Improve error handling if `lang_tags_map.py` is missing

If the developer forgot to run `make` to create `lang_tags_map.py`
we now print a message instead of reporting to Sentry.

Fixes #5343

feat(linux): Auto-generate reference help

Co-authored-by: Marc Durdin <marc@durdin.net>

chore(windows): add engine test framework

This is a rudimentary start to having unit tests for keyman32.

At present, it will build only in win32/debug and requires you
to manually run make -DDEBUG beforehand. The tests currently
run in Visual Studio and are not integrated.

auto: increment master version to 15.0.73

For auto-generating help files we need `buildtools`, so we can't
exclude it from source package. Also, we now include our version
of `help2man`, so we no longer need it as a build dependency,
but instead directly depend on `perl`.

During a package build we don't have access to `scripts/reconf.sh`.
However, we don't really need it since we already ran it before.
This change adds a `--no-reconf` flag that allows skipping
`reconf.sh`.

change(ios): setText now uses JSON serialization

refactor(web): osk key highlighting/preview behavior

refactor(web): OSK key source-code reorganization

chore(linux): Build also on riscv64 to facilitate migration on Ubuntu 🍒

fix(windows): restore endpoints for interface stability

fix(mac): kmp.inf is windows-1252

fix(mac): .kmx max file version is now 0x0E00 (14.0)

Fixes #5316.

Keyman for macOS did not recognise the updated version number 0x0E00,
which is version 14.0. There are no changes to the file format which
impact Keyman for macOS -- the only change is support for notany and
context for Keyman Engine for Web.

Relates to #5316.

Keyman for mac is still reading from kmp.inf, but was treating it as
UTF-8. However, it is windows-1252 encoding. This was stopping Keyman
from loading the file due to the presence of a (C) symbol.

Keyman for mac *should* be loading kmp.json. This needs to be addressed
as a separate issues.

Closes #4419

help2man is an improved version of the tool available on Linux. It
has a few bugs fixed.

help2md is based on help2man and converts the python --help and
--version output to a markdown help page.

(cherry picked from commit 5a58794f)

auto: increment master version to 15.0.72

chore(linux): Update changelogs to match Debian 🍒

feat(common): keyboard_processor wasm build

auto: increment master version to 15.0.71

The changelogs should match what got uploaded (and accepted) to
Debian so that the changelog reflects the upload history to Debian.

(cherry picked from commit f91b52d3)

fix(developer): kmconvert help match reality

fix(web): touch-move cancellation