ish: publish honest Android runtime packages

[isomorphisms]

Close the Android packaging gap needed by Cat Food PR #42 without aliasing ish to Grease, ysh, osh, or oils-for-unix.

This branch:

• generates Chez source from the maintained Ish/Idriç implementation at the pinned Idriç revision;
• uses Chez's supported cross-program xpatch path to compile that program for armv7le and arm64le;
• cross-builds a private Chez runtime plus libish_runtime.so and a native relocatable Android launcher with the NDK;
• packages only bin/ish as the public entrypoint;
• publishes immutable ARMv7 phone and AArch64 tablet prereleases when exact-head package jobs pass;
• records physical-device execution as PENDING rather than claiming it from cloud cross-build evidence.

The generated package is intended to become the two ish rows in Cat Food android/packages.tsv once the exact release assets and SHA-256 values exist.