docs: retain Android support in target policy

Author: cairn-intern

.coderabbit.yaml

@@ -31,7 +31,7 @@ reviews:
         Review tests for Bun test idioms, deterministic behavior, and meaningful coverage of safety decisions, provider/runtime flows, session events, and TUI command behavior.
     - path: "**/*.go"
       instructions: |
-        Do not request Plan 9 or other unsupported GOOS/GOARCH shims. Supported targets are the five release platforms (linux-x64, linux-arm64, macos-arm64, macos-x64, windows-x64). Other GOOS/GOARCH combinations are not a review criterion.
+        Do not request Plan 9 or other unsupported GOOS/GOARCH shims. The five native prebuilt release targets are linux-x64, linux-arm64, macos-arm64, macos-x64, and windows-x64. Android/Termux is also a supported runtime through the documented android-arm64 source build and Linux artifact fallback. Other GOOS/GOARCH combinations are not a review criterion.
   tools:
     github-checks:
       timeout_ms: 300000

AGENTS.md

@@ -81,12 +81,13 @@ These classes drive multi-round reviews. Fix them before requesting review:
   assert raw `t.TempDir()` spellings (`/var` vs `/private/var` on macOS, short
   paths on Windows). Prefer one cross-platform function with small `GOOS`
   checks over duplicated helpers that drift.
-- **Supported targets only:** The five release platforms in CONTRIBUTING.md
-  (`linux-x64`, `linux-arm64`, `macos-arm64`, `macos-x64`, `windows-x64`) are
-  the supported set. Other `GOOS`/`GOARCH` combinations, including `plan9`,
-  are unsupported and are not a review criterion. Do not block a PR for
-  failing to compile on an unsupported `GOOS`/`GOARCH`. Tests may use `plan9`
-  as a fixture for "unsupported".
+- **Supported targets only:** CONTRIBUTING.md names the five native prebuilt
+  release artifacts (`linux-x64`, `linux-arm64`, `macos-arm64`, `macos-x64`,
+  `windows-x64`) and the additional supported Android/Termux source-build and
+  artifact-fallback path. Other `GOOS`/`GOARCH` combinations, including
+  `plan9`, are unsupported and are not a review criterion. Do not block a PR
+  for failing to compile on an unsupported `GOOS`/`GOARCH`. Tests may use
+  `plan9` as a fixture for "unsupported".
 - **Security edges:** Keep secrets out of argv, env dumps, and logs. Redact
   success and error paths (including stderr). Fail closed on ownership, lease,
   and permission checks. Do not rely on pre-open path resolution

CONTRIBUTING.md

@@ -128,19 +128,28 @@ an approved feature.
 
 ## Supported platforms
 
-Zero is released for the same five platforms that `scripts/install.sh`,
-`scripts/install.ps1`, and the npm wrapper resolve, and that
-`.github/workflows/release-artifacts.yml` packages:
+Zero publishes five native prebuilt artifacts from
+`.github/workflows/release-artifacts.yml`:
 
 - `linux-x64` (`linux/amd64`)
 - `linux-arm64` (`linux/arm64`)
 - `macos-arm64` (`darwin/arm64`)
 - `macos-x64` (`darwin/amd64`)
 - `windows-x64` (`windows/amd64`)
 
-Other `GOOS`/`GOARCH` values, including Plan 9, are unsupported. They are not
-a review criterion. Do not block a pull request for failing to compile on an
-unsupported `GOOS`. Tests may use `plan9` as a fixture for an unsupported OS.
+The shell installer and npm wrapper resolve the applicable artifacts from that
+list. The PowerShell installer supports the published `windows-x64` artifact;
+there is no native Windows ARM64 artifact. Windows on ARM users can run the x64
+build under emulation or build from source.
+
+Android/Termux is also supported even though it has no distinct release
+artifact. The npm wrapper maps Android to the Linux artifact, and
+`docs/INSTALL.md` documents the native `android/arm64` source build needed on
+devices whose seccomp policy blocks the Linux build's syscall path.
+
+Other `GOOS`/`GOARCH` values, including Plan 9, are unsupported. They are not a
+review criterion. Do not block a pull request for failing to compile on an
+unsupported target. Tests may use `plan9` as a fixture for an unsupported OS.
 
 ## What We Prioritize