refactor: 将子模块转为普通目录，移除外部 git 依赖

- 移除 JEPA/lejepa-identifiability 子模块 gitlink
- 移除 research/multiply/MultiPLY 子模块 gitlink
- 删除 .gitmodules（不再有外部 URL 依赖）
- 两个目录内容作为普通文件纳入主仓库追踪
- 删除各自内部 .git 目录，消除嵌套 git 仓库

JEPA/lejepa-identifiability/experiments/slurm/launch_reacher_traj.sh

@@ -0,0 +1,36 @@
+#!/bin/bash
+#SBATCH --job-name=lejepa_traj
+#SBATCH --output=logs/traj_%A_%a.out
+#SBATCH --error=logs/traj_%A_%a.err
+#SBATCH --partition=gpuq
+#SBATCH --qos=slow_nice
+#SBATCH --gres=gpu:v100:1
+#SBATCH --cpus-per-task=4
+#SBATCH --mem=32G
+#SBATCH --time=24:00:00
+#SBATCH --array=0-6
+
+# Each task: prerender eval (skipped if exists) + 200k images for one delta,
+# then train 4 lambdas × 3 seeds × 3 inits = 36 training runs
+
+DELTAS=(1 2 4 8 16 32 64)
+DELTA=${DELTAS[$SLURM_ARRAY_TASK_ID]}
+
+H5_PATH="data/reacher.h5"
+
+eval "$(conda shell.bash hook)"
+conda activate pytorch
+export MUJOCO_GL=egl
+mkdir -p logs
+
+echo "Node: $(hostname) | delta=${DELTA} | Start: $(date)"
+
+# Step 1: Prerender (eval + this delta)
+python prerender.py eval
+python prerender.py traj --delta "${DELTA}" --h5_path "${H5_PATH}"
+
+# Step 2: Train
+python run_reacher.py --config configs/reacher.yaml \
+    --data_dir "data/reacher/traj/delta=${DELTA}"
+
+echo "Done: $(date)"