* require namespace of "raster" -- so that we can eventually move "raster" from Imports to Suggests
    - updated: `read_netCDF_as_raster()`, `get_xyspace()`
    - `read_netCDF(): wrap example code that uses "raster" in a require namespace condition

* example code and unit tests uses "terra" instead of "raster" where possible

* `get_xyspace()` can now handle "SpatRaster" ("terra" class) input

* `create_example_netCDFs()` uses "terra" instead of "raster" to create examples

- "consecutive_stopifnot_linter" renamed to "consecutive_assertion_linter"

- [unreachable_code_linter] Code inside a conditional loop with a deterministically false condition should be removed
- [unnecessary_nested_if_linter] Don't use nested `if` statements, where a single `if` with the combined conditional expression will do. For example, instead of `if (x) { if (y) { ... }}`, use `if (x && y) { ... }`.
- [keyword_quote_linter] Only quote named arguments to functions if necessary, i.e., if the name is not a valid R symbol (see ?make.names).
- [if_not_else_linter] In a simple if/else statement, prefer `if (A) x else y` to the less-readable `if (!A) y else x`.
- [implicit_assignment_linter] Avoid implicit assignments in function calls. For example, instead of `if (x <- 1L) { ... }`, write `x <- 1L; if (x) { ... }`.
- [indentation_linter] Indentation should be 8 spaces but is 6 spaces
- [scalar_in_linter] Use == to match length-1 scalars, not %in%. Note that == preserves NA where %in% does not.

- `as_points()`: now converts from/to "SpatVector"
- "sp" package is loaded via `requireNamespace()` if needed

…ate_nominal_resolution()

- switched algorithms, examples and unit tests from using "raster" package to "terra" and/or "stars" packages instead
- "RasterLayer" inputs are converted to "terra"'s "SpatRaster" (for now)

- small deviation in output from previous version due to new algorithms
- new (suggested) package dependencies on "lwgeom" and "units" for dealing with "stars" objects

- read_netCDF() can now use the "terra" package

-> make "raster" a "suggested" package

Use "terra" and "sf" packages instead of "raster" or "sp"

- addressing #18