Set up Cloud dev environment (Linux desktop) + AGENTS.md notes

[joei4cm]

Summary

Sets up and verifies the FlClash development environment for Linux desktop in the Cursor Cloud VM, and documents durable, non-obvious startup/run caveats in AGENTS.md for future agents.

No application code was changed — the only committed diff is the ## Cursor Cloud specific instructions section in AGENTS.md.

Environment installed (captured in VM snapshot)

• Flutter 3.44.4 stable (Dart 3.12.2), on PATH via /usr/local/bin symlinks
• Linux desktop toolchain: ninja-build, libgtk-3-dev, libayatana-appindicator3-dev, libkeybinder-3.0-dev, libstdc++-14-dev (needed so clang++ can link -lstdc++), plus existing cmake/clang/cargo/go 1.22.2
• core/Clash.Meta submodule initialized (GitHub SSH→token-HTTPS rewrite in global git config)

Startup update script (dependency refresh only)

git submodule update --init --recursive
flutter pub get

Verified

Task	Command	Result
Lint	flutter analyze --no-fatal-infos	Pass (info-only warnings)
Test	flutter test --reporter expanded	473 passed
Core build	make core-linux	Built libclash/linux/FlClashCore
App build	flutter build linux --debug	Bundle built
Run + hello world	flutter run -d linux	App runs; imported a Clash profile → core parsed it into the HELLO proxy group

Hello-world evidence

Imported a local Clash config profile; the core validated it and the Proxies page shows the HELLO group (hello-direct, DIRECT).

flclash_import_profile_hello_world.mp4

Dashboard Profile imported Proxies HELLO group

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