Add craft test command modeled on cargo test

[DaanyaalSobani]

Implements the proposal in #33.

What

Adds a craft test command that discovers .c / .cpp files in a project's tests/ directory and treats each one as an independent test binary — the cargo integration test model (one binary per file). craft test:

• Builds via the same flow as craft build (test targets are emitted in the generated CMakeLists.txt when tests/ exists, so craft build also picks them up).
• Runs each test binary, suppressing per-test output.
• Reports per-binary pass/fail and an aggregate summary.

Example

// tests/arithmetic.c
#include <assert.h>
#include "math.h"

int main(void) {
    assert(math_add(2, 3) == 5);
    return 0;
}

$ craft test
Building...
Project built successfully

running 3 tests
test adds_test ... ok
test multiplies_test ... ok
test subtracts_test ... ok

test result: ok. 3 passed; 0 failed

Options

• craft test <name> — substring filter (cargo-style)
• craft test --no-run — build test binaries without running them

Implementation

File	Change
include/test.h, src/test.c	New — test discovery, build via handle_build(), find each test binary across known multi-config layouts (build/, build/Debug/, build/Release/, build/MinSizeRel/, build/RelWithDebInfo/), report results
src/cmake.c	New write_tests() — emits an if(EXISTS tests/) block with file(GLOB ... CONFIGURE_DEPENDS). Library project types auto-link against the project library; executable projects do not
src/parser.c + include/parser.h	Registered test command + --no-run option
src/dispatcher.c	Routes test to handle_test
src/help.c	craft help test + entry in main help

Library vs. executable projects

• Library targets (static-library, shared-library, header-only): test files are auto-linked against the project library — write tests in terms of the project's public headers.
• Executable targets: test files are not auto-linked; cargo's equivalent for binary crates also requires explicit setup.

Trying it out

If you'd like to poke at this end-to-end without setting anything up yourself, I built a small public playground:

DaanyaalSobani/craft-playground — has a math/ static-library project with three passing tests and a repeatable bash harness at scripts/test_craft_test.sh that exercises six scenarios (22 checks total: all-passing, filter, --no-run, known-failing test, missing tests/, no-match filter). Points at this branch's craft.exe by default; override via the CRAFT env var.

Scope

Deliberately matches cargo's integration test model only. Per-function #[test]-style granularity (one file, many independently-reported tests) is called out as a future direction in #33 — happy to layer that on later via either a small bundled framework or a [test] section in craft.toml if you'd prefer.

Testing

Tested on Windows 11 / MSVC 19.42 / CMake 4.3.2 against the playground harness — 22/22 checks pass.