v0.4.2

fix: wrapper script handles LD_LIBRARY_PATH for Mojo runtime libs (#2)

* fix: wrapper script handles LD_LIBRARY_PATH for Mojo runtime libs

Mojo AOT binaries require libKGENCompilerRTShared.so in LD_LIBRARY_PATH.
Instead of requiring users to set this manually, install two files:
- mojo-pkg-bin: the compiled binary
- mojo-pkg: a bash wrapper that auto-locates Mojo runtime libs from any
  pixi env under ~/mojo_pg/ and sets LD_LIBRARY_PATH before exec

Updated: build_and_run.sh, scripts/install.sh, release.yml, README.md

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* fix: wrapper now searches CWD, PIXI_PROJECT_ROOT, and $HOME for runtime libs

The previous wrapper only searched fixed ~/mojo_pg/ paths, which fails in CI.
New search order:
1. System ldconfig (already findable — no-op)
2. Walk up from CWD looking for .pixi/envs/default/lib (works for any pixi project, including CI)
3. PIXI_PROJECT_ROOT env var (set by pixi run)
4. Known ~/mojo_pg/ fixed paths (local dev fallback)
5. find $HOME as last resort

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

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Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>