feat: introduce dedicated Antigravity CLI (agy) path setting with multi-architecture eligibility patcher

[yhan-sun]

💡 Background

In newer versions of the Google Antigravity CLI binary client (agy / antigravity.exe 1.1.2 and above), a local Eligibility Check is enforced. If the user's Google account is not configured as eligible on the server, the client intercepts inputs in the interactive terminal (TUI) and prompts:
Your current account is not eligible for Antigravity...

This prevents unauthorized accounts from starting local conversations. This Pull Request implements an instruction-level pattern matching patcher that dynamically bypasses this local gate without modifying network configurations.

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🛠️ Key Changes

1. Dedicated CLI Path Settings:

   • Introduced a new antigravity_cli_executable configuration field to the backend configuration schema (AppConfig) and TypeScript types (types/config.ts).
   • Added a dedicated setting input under the "Advanced Settings" UI panel for the CLI path. The application now separates paths for Antigravity Classic, Antigravity IDE, and Antigravity CLI (agy).
   • Moved the eligibility check bypass patching section to reside under the newly added CLI Path configuration since the patching applies only to the agy binary.

2. Rust Backend (src-tauri):

   • Added the Tauri command patch_agy_binary (patch.rs).
   • Multi-Architecture Support:
     • macOS (ARM64): Scans machine code by 4-byte (32-bit aligned) strides to dynamically locate the userInputLoop instruction pattern (ldrb, tbnz, ldr, and cbz) and overwrites the conditional branch cbz to b (unconditional jump to the send path) to bypass the gate. Also handles macOS ad-hoc code re-signing.
     • Windows/Linux (x86_64 PE/ELF): Scans for the x86_64 verification gate pattern: cmpb $0x0, (%r12), jne label, leaq rip_off, %rax, mov $0x18, %ebx. Dynamically replaces the conditional jump instruction jne with NOP (6 bytes of 0x90) to bypass the gate.
   • Handles backing up the binary to .bak.
   • Added get_antigravity_cli_path for detecting standard installer locations (~/.local/bin/agy or environment PATH).

3. React Frontend UI (src):

   • Configured the Advanced Settings tab in Settings.tsx to integrate selection, detection, clearing, and triggering of the patching command against the CLI path.
   • Added translation keys for Chinese and English.

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🧪 Tested & Verified

• Platform: macOS (ARM64) & Windows (x64)
• Target Binary: Antigravity CLI 1.1.2
• Result: Successfully bypassed the Eligibility Check failed window and restored fully working AI interactions in the terminal for standard Google accounts.