Homebrew dependency root packages

[brandonpayton]

Summary

• Add Kandelo Homebrew formulae for openssl, libcxx, libxml2, libpng, libcurl, and ncurses.
• Update package build scripts so Homebrew and package-resolver builds share SDK activation, arch handling, work dirs, and explicit unsupported wasm64 status where needed.
• Extend bottle/sidecar generation to support dependency bottle pouring, incremental sidecar preservation, and Node VFS smokes for the new packages.
• Document the dependency-root package status and artifact expectations.

Verification

• Bottle builds/tests: 11 passed, 0 failed, 0 skipped for zlib plus the six target packages/arches.
• Sidecar validation: 7 packages, 11 bottles, 11 link manifests, 11 provenance reports validated.
• Node VFS smokes: wasm32 12 passed/0 failed/0 skipped; wasm64 6 passed/0 failed/0 skipped.
• Browser smoke status: 11 skipped with recorded reason; these sidecars declare node-only runtime/browser_compatible=false.
• Upstream full-test status: 6 skipped with recorded reason; formula tests plus Kandelo Node consumer smokes were run instead.
• Required gates: ABI check passed; cargo test -p kandelo --target aarch64-apple-darwin --lib passed (963/0); host vitest passed (98 files passed, 25 skipped; 779 passed, 2 expected-fail, 111 skipped); libc suite exited 0 with 302 pass, 20 xfail, 1 flake-pass, 1 documented local timeout for regression/raise-race; POSIX suite exited 0 with 174 pass, 3 xfail, 2 unsupported skips.
• Focused tooling: cargo test -p xtask --target aarch64-apple-darwin homebrew passed (18/0); shell syntax checks and formula Ruby syntax checks passed.

Durable outcome lists/logs are under test-runs/kd-zq4n/ in the bead worktree.