[FEATURE] Add support for linux-loong64 (LoongArch64) platform！！

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• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Claude Code currently does not support the linux-loong64 (LoongArch64) architecture. When attempting to install Claude Code on a Loongson machine running Linux (loong64), the postinstall script exits with the following error:

[@anthropic-ai/claude-code postinstall] Unsupported platform: linux loong64
  Supported: darwin-arm64, darwin-x64, linux-x64, linux-arm64, linux-x64-musl,
  linux-arm64-musl, linux-arm64-android, linux-x64-android, freebsd-x64,
  freebsd-arm64, win32-x64, win32-arm64

LoongArch (LoongArch64 / loong64) is a RISC ISA developed by Loongson Technology and is gaining traction in China's domestic hardware ecosystem. It is supported by mainstream Linux distributions (e.g., Debian, Arch Linux, Gentoo) and the Node.js runtime already provides official builds for this architecture (node-v22.x-linux-loong64). However, Claude Code's native binaries are not compiled for this target, making installation impossible.

Proposed Solution

Add linux-loong64 as a supported target platform for Claude Code by:

1. Including linux-loong64 in the CI/CD build matrix to compile and package the necessary native binaries for this architecture.
2. Updating the platform detection logic in install.cjs to recognize linux loong64 as a valid target.
3. Publishing the linux-loong64 binary alongside existing platform artifacts in future releases.

As a reference, Node.js already maintains official loong64 builds, so the toolchain foundation is available. This change would enable Claude Code to reach a growing segment of Linux users on Loongson hardware.

Alternative Solutions

_No response_

Priority

High - Significant impact on productivity

Feature Category

CLI commands and flags

Use Case Example

A developer in China is working on a software project using a Loongson 3A6000-based workstation running Loongnix (a Loongson-maintained Linux distribution based on Debian). The machine runs Node.js v22 (linux-loong64 build) and has internet access.
Step-by-step scenario:
1.The developer sees that Claude Code is available as an AI-powered coding assistant and wants to integrate it into their daily workflow.
2.They install Node.js v22 for loong64 from the official Node.js release page — this works without issue.
3.They attempt to install Claude Code via npm:

npm install -g @anthropic-ai/claude-code

4.The postinstall script runs and immediately fails:

[@anthropic-ai/claude-code postinstall] Unsupported platform: linux loong64

The developer is completely blocked — there is no workaround, no fallback, and no way to proceed on this machine.

With linux-loong64 support added, step 4 would succeed, and the developer could use Claude Code just like any user on x64 or ARM64 Linux — with no extra configuration required.

Additional Context

_No response_