shell: implement 'true' and 'false' builtin commands

[nektro]

progress on #9716

cross-referenced with:
https://git.savannah.gnu.org/cgit/coreutils.git/tree/src/true.c
https://git.savannah.gnu.org/cgit/coreutils.git/tree/src/false.c

[github-actions]

❌ @nektro 3 files with test failures on linux-x64-baseline:

• test/integration/next/default-pages-dir/test/next-build.test.ts SIGTERM
• test/js/node/watch/fs.watchFile.test.ts 1 failing
• test/napi/napi.test.ts 6 failing

View test output

^{#4e3415454fc9a9c48674c8769b7658e0e4c331e1}

[github-actions]

❌ @nektro 4 files with test failures on linux-x64:

• test/integration/next/default-pages-dir/test/next-build.test.ts SIGTERM
• test/js/node/watch/fs.watchFile.test.ts 2 failing
• test/napi/napi.test.ts 6 failing
• test/regression/issue/09041.test.ts 1 failing

View test output

^{#4e3415454fc9a9c48674c8769b7658e0e4c331e1}

[github-actions]

❌🪟 @nektro, there are 8 test regressions on Windows x86_64

• test\cli\install\bunx.test.ts
• test\cli\install\registry\bun-install-registry.test.ts
• test\js\bun\glob\scan.test.ts
• test\js\node\dns\node-dns.test.js
• test\js\third_party\esbuild\esbuild-child_process.test.ts
• test\js\web\fetch\body-stream.test.ts
• test\regression\issue\09041.test.ts
• test\js\third_party\postgres\postgres.test.ts

Full Test Output

[paperdave]

winner

[github-actions]

❌ @nektro 4 files with test failures on bun-darwin-aarch64:

• test/cli/install/registry/bun-install-registry.test.ts SIGTERM
• test/integration/next/default-pages-dir/test/next-build.test.ts SIGTERM
• test/js/bun/http/serve.test.ts 11 failing
• test/js/bun/test/test-test.test.ts 1 failing

View test output

^{#4e3415454fc9a9c48674c8769b7658e0e4c331e1}

[github-actions]

❌ @nektro 5 files with test failures on bun-darwin-x64:

• test/integration/next/default-pages-dir/test/dev-server.test.ts 1 failing
• test/integration/next/default-pages-dir/test/next-build.test.ts SIGTERM
• test/js/bun/spawn/spawn.test.ts SIGTERM
• test/js/third_party/prisma/prisma.test.ts SIGABRT
• test/js/web/workers/worker.test.ts 1 failing

View test output

^{#4e3415454fc9a9c48674c8769b7658e0e4c331e1}

[Jarred-Sumner]

nice