qgisprocess 0.3.0

Enhancements

QGIS or third-party providers can expose deprecated algorithms that may be removed from future versions. {qgisprocess} now handles these algorithms explicitly (#198):
- qgis_run_algorithm() and other functions (such as qgis_show_help() and qgis_get_description()) will warn if a deprecated algorithm is passed (issues #193, #194).
- qgis_search_algorithms() now excludes deprecated algorithms by default; they can still be included by setting the include_deprecated argument to TRUE.
- qgis_algorithms() can optionally restrict its results to non-deprecated algorithms (set the include_deprecated argument to FALSE). By default they are included, just as before.
More consistent and intuitive handling of JSON input / output user settings (#195, #196; see ?qgis_using_json_output).

Fix bug in support for environment variable R_QGISPROCESS_DETECT_NEWER_QGIS (#197).
Fix unit test to comply with {terra} > 1.7-65 (#202).

Add vector support for {terra} (#184). This makes it possible to use SpatVector or SpatVectorProxy objects as input arguments, and to coerce processing results to SpatVector or SpatVectorProxy.
qgis_detect_windows_paths() and qgis_detect_macos_paths() put paths at the top that contain a QGIS version string and these paths are sorted according to decreasing QGIS version (#189). This lets qgis_configure() select the newest QGIS version among qgis_process file paths that have a version string. Furthermore, a wrapper qgis_detect_paths() has been added that works on both Windows and macOS (#192).

Allow half-configured states with abundant messages, so that remaining functionality can be used in debugging or even for some real stuff (#177).
qgis_run_algorithm() documentation gains a section on QGIS models and scripts (8a20669).
An option qgisprocess.detect_newer_qgis is available (mirrored by environment variable R_QGISPROCESS_DETECT_NEWER_QGIS) for Windows and macOS (#192). If set as TRUE, during package loading {qgisprocess} will check whether a more recent (standalone) QGIS version is also installed while the package cache still dictates to use an older version. In this specific scenario a question will be asked to switch to the newer version. Without setting this option default behaviour remains in place, i.e. the user must manually intervene either by running qgis_configure(), by setting the qgisprocess.path option, or by uninstalling the older QGIS version.
Solve a CRAN check error on r-oldrel-macos-x86_64, by adding support for {stars} 0.5-5 (#175).

Initial CRAN release.
While the package incubated as a development version for a few years, quite a few namespace changes have been made more recently (#153). Old function names still work but these are deprecated. They will be dropped at a later stage.