Fold LEGACY into the generation folders

The LEGACY copies of HexapodRobot, Hexapod_NEW, Hexapod_Teensy and the old remote sketch were identical to the imported repos and are removed. The old Nextion design moves to 2019-teensy-nrf24/remote-nextion/, the 2019 remote case files to 2019-teensy-nrf24/remote-case/. Paths in CLAUDE.md, READMEs, remote/ comments, sim/build.ps1, the Unity DLL message and .vscode/settings.json now point to the new places. robot/ is not touched (its CLAUDE.md asks to check with the owner first).

2026-current/README.md

@@ -9,10 +9,14 @@ remote/                    remote firmware: 2 x 3-axis sticks, MPU6050 tilt, Nex
 shared/                    HexapodProtocol: the CmdPacket wire format + radio settings used by both
 sim/                       the unchanged robot firmware compiled into a DLL for the simulation
 Hexapod_Simulation_Unity/  Unity project that runs that DLL on the 3D model
-LEGACY/                    older material kept for reference
+hardware/fusion360/        Fusion 360 designs: body, legs, servo, servo horn, remote case
 scripts/                   PlatformIO helper (per-environment sketch folder)
 ```
 
+This is the `2026-current/` folder of the hexapod-robot repo; the earlier
+generations (2009 onwards) are in the folders next to it, see
+[../README.md](../README.md).
+
 ## Build (PlatformIO)
 
 ```
@@ -24,7 +28,7 @@ pio device monitor -e robot
 
 ## Simulation
 
-From the repo root in PowerShell (the dev PC is Windows):
+From this `2026-current` folder in PowerShell (the dev PC is Windows):
 
 ```
 .\sim\build.ps1            # build hexapod_sim.dll + run the headless firmware checks