Set up dev environment (Linux) + fix CMake configure break

AGENTS.md

@@ -0,0 +1,41 @@
+# AGENTS.md
+
+## Cursor Cloud specific instructions
+
+LabRecorder is a C++/Qt6 desktop app (plus a `LabRecorderCLI` command-line recorder and an
+in-tree `xdfwriter` static library + `testxdfwriter` test exe) for recording Lab Streaming
+Layer (LSL) streams to `.xdf` files. There are no databases/servers; "services" here are just
+the recorder binaries plus at least one live LSL stream to record. Build is CMake-only;
+standard build commands are documented in `BUILD.md` and `CMakePresets.json`.
+
+### Build / configure (Linux)
+- Use the `linux-gcc-release` preset:
+  - `cmake --preset linux-gcc-release`
+  - `cmake --build --preset linux-release -j`
+- Binaries land in `out/build/linux-gcc-release/` (`LabRecorder`, `LabRecorderCLI`,
+  `xdfwriter/testxdfwriter`).
+- `liblsl` is installed system-wide (deb), so `find_package(LSL)` resolves via
+  `/usr/lib/cmake/LSL` with no `LSL_INSTALL_ROOT` needed.
+
+### Non-obvious caveats
+- The default C++ compiler (`/usr/bin/c++`) is **clang**, which uses the gcc-14 toolchain and
+  therefore needs `libstdc++-14-dev` (the update script installs it). Without it, even the
+  CMake compiler check fails with `cannot find -lstdc++`.
+- The committed `LabRecorder.cfg` (copied next to the GUI binary at build time) has a
+  Windows `StudyRoot`/save path (`E:/Dropbox...`) that is not writable on Linux. Before
+  recording with the GUI, set the **Study Root** field to a writable dir (e.g. `/tmp/lr_recordings`)
+  and a simple **File Name/Template** (e.g. `gui_test.xdf`). The GUI auto-creates the directory.
+- `CMakeUserPresets.json` only defines Windows presets; ignore it on Linux.
+
+### Running / testing end-to-end
+- A running X display is available at `DISPLAY=:1` (TigerVNC + xfce4); launch the GUI with
+  `DISPLAY=:1 ./LabRecorder`.
+- To exercise the recorder you need a live LSL stream. There are no bundled example senders,
+  so create a tiny one against the installed `liblsl` headers (`/usr/include/lsl_cpp.h`,
+  link with `-llsl`) that opens an `lsl::stream_outlet` and pushes samples.
+- CLI flow: `./LabRecorderCLI out.xdf 'type="EEG"'` resolves matching streams, records, and
+  stops on Enter (so e.g. `(sleep 5; echo) | ./LabRecorderCLI ...` records ~5s).
+- Verify a recording by checking the file starts with the `XDF:` magic and contains the
+  expected stream name/type.
+- Unit check: run `out/build/linux-gcc-release/xdfwriter/testxdfwriter` (exit 0 = pass; it
+  writes a sample `test.xdf`).

CMakeLists.txt

@@ -126,10 +126,6 @@ add_executable(LabRecorderCLI MACOSX_BUNDLE
 	src/clirecorder.cpp
 	src/recording.h
 	src/recording.cpp
-add_executable(LabRecorderCLI
-    src/clirecorder.cpp
-    src/recording.h
-    src/recording.cpp
 )
 else()
 add_executable(LabRecorderCLI