Clean repo for open source release

Remove build artifacts, dev tool configs, unused dependencies,
and third-party source dumps. Add proper README, update .gitignore,
clean up Makefile.

src/main/java/com/tiedup/remake/blocks/BlockCellDoor.java

@@ -0,0 +1,34 @@
+package com.tiedup.remake.blocks;
+
+import net.minecraft.world.level.block.DoorBlock;
+import net.minecraft.world.level.block.SoundType;
+import net.minecraft.world.level.block.state.BlockBehaviour;
+import net.minecraft.world.level.block.state.properties.BlockSetType;
+import net.minecraft.world.level.material.MapColor;
+
+/**
+ * Cell Door Block - Iron-like door that cannot be opened by hand.
+ *
+ * Phase 16: Blocks
+ *
+ * Features:
+ * - Cannot be opened by clicking (requires redstone)
+ * - Uses iron door behavior
+ * - Sturdy construction
+ *
+ * Based on original BlockKidnapDoorBase from 1.12.2
+ */
+public class BlockCellDoor extends DoorBlock {
+
+    public BlockCellDoor() {
+        super(
+            BlockBehaviour.Properties.of()
+                .mapColor(MapColor.METAL)
+                .strength(5.0f, 45.0f)
+                .sound(SoundType.METAL)
+                .requiresCorrectToolForDrops()
+                .noOcclusion(),
+            BlockSetType.IRON // J'ai remis moi même
+        );
+    }
+}