ENH: Add 'start' and additional tasks to Pixi manifest

* Separate tasks out in Pixi manifest to allow for running build, testing,
  and install tasks separately. Add canonical 'start' task to build and
  install software. Add 'test' task that will do a clean build and run
  ctests.
* Update task name from 'build' to 'test' in README.
* Remove 'rm' of build directory from 'build' task to allow for potentially
  skipping files that do not need to be regenerated and to give user slightly
  more control.

Author: matthewfeickert

README.md

@@ -332,7 +332,7 @@ export PATH="/root/.pixi/bin:$PATH"
 cd user/
 git clone git@github.com:prashjha/PeriDEM.git
 cd PeriDEM/
-pixi run build
+pixi run test
 ```
 
 ### Future plans

pixi.toml

@@ -4,11 +4,9 @@ name = "PeriDEM"
 platforms = ["linux-64", "osx-arm64"]
 version = "v0.2.1"
 
-# Currently can't install, only build?
-# c.f. https://github.com/prashjha/PeriDEM/blob/8f73cbd12fbf8d483bb46670661f9f2641d03c37/README.md?plain=1#L264
 [tasks.build]
+description = "Build PeriDEM from local source"
 cmd = """
-rm -rf build && \
 cmake   -DEnable_Documentation=OFF \
         -DEnable_Tests=ON \
         -DEnable_High_Load_Tests=OFF \
@@ -20,10 +18,25 @@ cmake   -DEnable_Documentation=OFF \
         -S . \
         -B build && \
 cmake build -LH && \
-cmake --build build --clean-first --parallel "$(nproc --ignore=2)" && \
-ctest --verbose --test-dir build/
+cmake --build build --clean-first --parallel "$(nproc --ignore=2)"
 """
 
+[tasks.ctest]
+description = "Run tests with ctest"
+cmd = "ctest --verbose --test-dir ./build/"
+
+[tasks.install-peridem]
+description = "Install PeriDEM under CMAKE_INSTALL_PREFIX defined in build"
+cmd = "cmake --install build"
+
+[tasks.start]
+description = "Build and install PeriDEM"
+depends-on = ["build", "install-peridem"]
+
+[tasks.test]
+description = "Do a clean build of PeriDEM and run ctest tests"
+depends-on = ["build", "ctest"]
+
 [dependencies]
 cxx-compiler = ">=1.11.0,<2"
 cmake = ">=4.2.1,<5"