docs: add Termux setup guide

[Brajesh2022]

Summary

• Add docs/termux.md with a Termux setup guide for running the Linux ARM64 Antigravity CLI on Android/Termux.
• Link the Termux guide from the README top links and Installation section.

Why

Termux users can hit several platform compatibility issues when running the Linux ARM64 agy binary directly on Android, including ARM64 VA39/TCMalloc assumptions, Android seccomp blocking faccessat2, glibc libc.so linker-script loading, Termux LD_PRELOAD pollution, DNS resolver discovery, TLS certificate discovery, and shell command hashing.

This guide documents the currently working setup and troubleshooting checks without changing the CLI binary, installer, or runtime behavior for existing platforms.

Maintainer notes

• This is documentation-only.
• The guide explicitly calls out that the VA39 binary patch is a practical workaround, not a substitute for an official supported build.
• The documented patch script is conservative and warns if expected instruction patterns are missing.
• The guide also lists preferred upstream fixes, such as an official VA39-compatible Linux ARM64 build, runtime allocator configuration, a non-TCMalloc build, or an official Android/Termux-compatible build.

Validation

• Ran git diff --cached --check before commit.
• No runtime tests were run because this repository currently only contains documentation/assets and this change is docs-only.

[Brajesh2022]

Update: confirmed working on Chromebook/Crostini too, see the simplified Chromebook-only script in the comment on #21 (comment)

[MichaelWS]

this is excellent. Thanks for fixing on chromebook.
this is the chromebook only script ->
https://gist.github.com/MichaelWS/9e97f791db704f078dcf66d0dd9245ee

[MichaelWS]

do you have to login each time? chromebook/crostini isn't saving my login credentials

[lesteral]

@MichaelWS - for me, this issue has been fixed in v1.0.1, released today. See the first bullet below.

[~] agy changelog
1.0.1:
· Fixed OAuth token persistence and authentication hangs.
· Fixed Windows log redirection and resizing issues. Resolved a critical bug where logs were not redirected correctly on Windows, which previously caused the terminal to swallow window resize events and shut down slowly.
· Added `proceed-in-sandbox` tool permission mode. Auto-approves terminal commands that run inside the secure sandbox, requesting manual approval only when a command attempts to bypass the sandbox.
· Integrates consumer/free-tier onboarding directly into the CLI.
· Added plugin discovery for skills and agents. Automatically scans installed plugin directories to make custom skills and specialized agents available for execution in the CLI.
· Fixed pasted text line counting. Corrected line counting for user inputs to ensure extremely long inputs are correctly folded into a `[Pasted text #X +Y lines]` placeholder to keep the viewport clean.
· Fixed onboarding stability. Resolved a race condition where a concurrent terminal resize event during onboarding could revert the UI to a blank onboarding screen.
· Moves the **terminal** color scheme to the top of the selection list, making it the default choice during onboarding and in `/settings`.
· Improved `/usage` and `/quota` commands. Forces a real-time reload of model configuration and remaining quotas, allowing you to see updated real-time consumption statistics immediately.
· Improved step rendering layout. Calculates available terminal width dynamically and uses middle-truncation (`/foo/.../bar`) for file path tools to prevent layout shifting on narrow screens.
· Improved session deletion keybinding in `/resume`. Changed the shortcut from `ctrl+d` to `ctrl+delete` to resolve conflicts with the global exit keybinding (`ctrl+d` `ctrl+d`) and preserve Emacs-style forward-delete in search input fields.
· Restored automatic table wrapping, preventing long cells inside markdown tables from being truncated.
· Resolved an issue where deleted files (represented by `+++ /dev/null`) had their deletion lines incorrectly merged into the previous file's diff.

1.0.0:
· Initial release of the Antigravity CLI.

[Brajesh2022]

do you have to login each time? chromebook/crostini isn't saving my login credentials

No, I never faced such issues even in version 1, but I know some guys were experiencing that issue in version 1.0.0

[MichaelWS]

scratch that. This is fixed.

[7ui77]

I have updated the Termux setup guide to support devices with older CPU architectures that lack LSE (Large System Extensions). Without LSE, running the patched binary directly under glibc triggers an immediate SIGILL (Illegal Instruction) crash.

Here is a summary of the updates made to the guide:

1. Requirements: Added qemu-user-aarch64 to the package installation list (pkg install qemu-user-aarch64).

2. Wrapper Script: Updated the template to route execution through qemu-aarch64 inside proot:

   ```bash
   exec /data/data/com.termux/files/usr/bin/proot \
     -b /data/data/com.termux/files/usr/etc/resolv.conf:/etc/resolv.conf \
   
     /data/data/com.termux/files/usr/bin/qemu-aarch64 \
     $G/ld-linux-aarch64.so.1 --library-path $S:$G \
     /data/data/com.termux/files/home/.local/bin/agy.va39 "$@"