v0.1.7

feat: add dedicated Android builds for Termux compatibility

Termux requires GOOS=android binaries instead of GOOS=linux for
proper system call compatibility. While both work similarly, Android
binaries handle Termux environment correctly.

Changes:
- Added android-arm64 and android-armv7 to release workflow
- Install script auto-detects Termux and downloads android binary
- Updated README with correct binary names for Termux

This fixes binary compatibility issues where linux binaries don't
work properly in Termux but locally-built binaries do.

Note: One-line installer now downloads clipilot-android-arm64 on
Termux instead of clipilot-linux-arm64.