feat(bedrock): Initial inventory setup (#2215)

* Initial asset prep, and `CItemRegistry` packet (vanilla; no Java fixes).

* Fix definition component NBTs.

* Packet fixes and dummy stick.

* Map actual player inventory & add stack UIDs

* Cleanup

* Update assets README

assets/bedrock/README.md

@@ -0,0 +1,15 @@
+# Bedrock Assets
+
+This directory contains a number of different data files used to help support connecting via Bedrock Edition clients (including Java => Bedrock remapping).
+
+- `block_states.nbt`
+    - mined from BDS (file hosted at [pmmp/BedrockData](https://github.com/pmmp/BedrockData/blob/master/canonical_block_states.nbt), `canonical_block_states.nbt`)
+    - Provides a listing of all blocks and block states that exist in Bedrock. Used to build a mapping from Java block states to Bedrock ones by matching (string) identifiers and data components.
+- `item_components.nbt`
+    - mined from BDS (file hosted at [CloudburstMC/Data](https://github.com/CloudburstMC/Data))
+- `runtime_item_states.nbt`
+    - mined from BDS (file hosted at [CloudburstMC/Data](https://github.com/CloudburstMC/Data))
+- `item_data_overrides.json`
+    - adapted from `GeyserMC/mappings` `items.json`.
+    - Strips everything except the `bedrock_data` field (making it the value of each corresponding top-level key), omitting any `0` values.
+    - Most of `items.json` is automatically generated, but that value appears to be manually maintained by the Geyser team. We separate that out for our own use, while keeping the rest generated.

assets/bedrock/item_data_overrides.json

@@ -0,0 +1,204 @@
+{
+    "granite": 1,
+    "polished_granite": 2,
+    "diorite": 3,
+    "polished_diorite": 4,
+    "andesite": 5,
+    "polished_andesite": 6,
+    "spruce_planks": 1,
+    "birch_planks": 2,
+    "jungle_planks": 3,
+    "acacia_planks": 4,
+    "dark_oak_planks": 5,
+    "spruce_log": 1,
+    "birch_log": 2,
+    "jungle_log": 3,
+    "dark_oak_log": 1,
+    "stripped_oak_wood": 8,
+    "stripped_spruce_wood": 9,
+    "stripped_birch_wood": 10,
+    "stripped_jungle_wood": 11,
+    "stripped_acacia_wood": 12,
+    "stripped_dark_oak_wood": 13,
+    "spruce_wood": 1,
+    "birch_wood": 2,
+    "jungle_wood": 3,
+    "acacia_wood": 4,
+    "dark_oak_wood": 5,
+    "spruce_leaves": 1,
+    "birch_leaves": 2,
+    "jungle_leaves": 3,
+    "dark_oak_leaves": 1,
+    "wet_sponge": 1,
+    "light_gray_wool": 8,
+    "purpur_pillar": 2,
+    "spruce_fence": 1,
+    "birch_fence": 2,
+    "jungle_fence": 3,
+    "acacia_fence": 4,
+    "dark_oak_fence": 5,
+    "brown_mushroom_block": 14,
+    "red_mushroom_block": 14,
+    "mossy_cobblestone_wall": 1,
+    "brick_wall": 6,
+    "prismarine_wall": 11,
+    "red_sandstone_wall": 12,
+    "mossy_stone_brick_wall": 8,
+    "granite_wall": 2,
+    "stone_brick_wall": 7,
+    "nether_brick_wall": 9,
+    "andesite_wall": 4,
+    "red_nether_brick_wall": 13,
+    "sandstone_wall": 5,
+    "end_stone_brick_wall": 10,
+    "diorite_wall": 3,
+    "orange_terracotta": 1,
+    "magenta_terracotta": 2,
+    "light_blue_terracotta": 3,
+    "yellow_terracotta": 4,
+    "lime_terracotta": 5,
+    "pink_terracotta": 6,
+    "gray_terracotta": 7,
+    "light_gray_terracotta": 8,
+    "cyan_terracotta": 9,
+    "purple_terracotta": 10,
+    "blue_terracotta": 11,
+    "brown_terracotta": 12,
+    "green_terracotta": 13,
+    "red_terracotta": 14,
+    "black_terracotta": 15,
+    "orange_carpet": 1,
+    "magenta_carpet": 2,
+    "light_blue_carpet": 3,
+    "yellow_carpet": 4,
+    "lime_carpet": 5,
+    "pink_carpet": 6,
+    "gray_carpet": 7,
+    "light_gray_carpet": 8,
+    "cyan_carpet": 9,
+    "purple_carpet": 10,
+    "blue_carpet": 11,
+    "brown_carpet": 12,
+    "green_carpet": 13,
+    "red_carpet": 14,
+    "black_carpet": 15,
+    "orange_stained_glass": 1,
+    "magenta_stained_glass": 2,
+    "light_blue_stained_glass": 3,
+    "yellow_stained_glass": 4,
+    "lime_stained_glass": 5,
+    "pink_stained_glass": 6,
+    "gray_stained_glass": 7,
+    "light_gray_stained_glass": 8,
+    "cyan_stained_glass": 9,
+    "purple_stained_glass": 10,
+    "blue_stained_glass": 11,
+    "brown_stained_glass": 12,
+    "green_stained_glass": 13,
+    "red_stained_glass": 14,
+    "black_stained_glass": 15,
+    "orange_stained_glass_pane": 1,
+    "magenta_stained_glass_pane": 2,
+    "light_blue_stained_glass_pane": 3,
+    "yellow_stained_glass_pane": 4,
+    "lime_stained_glass_pane": 5,
+    "pink_stained_glass_pane": 6,
+    "gray_stained_glass_pane": 7,
+    "light_gray_stained_glass_pane": 8,
+    "cyan_stained_glass_pane": 9,
+    "purple_stained_glass_pane": 10,
+    "blue_stained_glass_pane": 11,
+    "brown_stained_glass_pane": 12,
+    "green_stained_glass_pane": 13,
+    "red_stained_glass_pane": 14,
+    "black_stained_glass_pane": 15,
+    "orange_shulker_box": 1,
+    "magenta_shulker_box": 2,
+    "light_blue_shulker_box": 3,
+    "yellow_shulker_box": 4,
+    "lime_shulker_box": 5,
+    "pink_shulker_box": 6,
+    "gray_shulker_box": 7,
+    "light_gray_shulker_box": 8,
+    "cyan_shulker_box": 9,
+    "purple_shulker_box": 10,
+    "blue_shulker_box": 11,
+    "brown_shulker_box": 12,
+    "green_shulker_box": 13,
+    "red_shulker_box": 14,
+    "black_shulker_box": 15,
+    "orange_concrete": 1,
+    "magenta_concrete": 2,
+    "light_blue_concrete": 3,
+    "yellow_concrete": 4,
+    "lime_concrete": 5,
+    "pink_concrete": 6,
+    "gray_concrete": 7,
+    "light_gray_concrete": 8,
+    "cyan_concrete": 9,
+    "purple_concrete": 10,
+    "blue_concrete": 11,
+    "brown_concrete": 12,
+    "green_concrete": 13,
+    "red_concrete": 14,
+    "black_concrete": 15,
+    "orange_concrete_powder": 1,
+    "magenta_concrete_powder": 2,
+    "light_blue_concrete_powder": 3,
+    "yellow_concrete_powder": 4,
+    "lime_concrete_powder": 5,
+    "pink_concrete_powder": 6,
+    "gray_concrete_powder": 7,
+    "light_gray_concrete_powder": 8,
+    "cyan_concrete_powder": 9,
+    "purple_concrete_powder": 10,
+    "blue_concrete_powder": 11,
+    "brown_concrete_powder": 12,
+    "green_concrete_powder": 13,
+    "red_concrete_powder": 14,
+    "black_concrete_powder": 15,
+    "brain_coral": 1,
+    "bubble_coral": 2,
+    "fire_coral": 3,
+    "horn_coral": 4,
+    "dead_brain_coral": 9,
+    "dead_bubble_coral": 10,
+    "dead_fire_coral": 11,
+    "dead_horn_coral": 12,
+    "dead_tube_coral": 8,
+    "piston": 1,
+    "sticky_piston": 1,
+    "dispenser": 3,
+    "dropper": 3,
+    "cocoa_beans": 3,
+    "orange_bed": 1,
+    "magenta_bed": 2,
+    "light_blue_bed": 3,
+    "yellow_bed": 4,
+    "lime_bed": 5,
+    "pink_bed": 6,
+    "gray_bed": 7,
+    "light_gray_bed": 8,
+    "cyan_bed": 9,
+    "purple_bed": 10,
+    "blue_bed": 11,
+    "brown_bed": 12,
+    "green_bed": 13,
+    "red_bed": 14,
+    "black_bed": 15,
+    "white_banner": 15,
+    "orange_banner": 14,
+    "magenta_banner": 13,
+    "light_blue_banner": 12,
+    "yellow_banner": 11,
+    "lime_banner": 10,
+    "pink_banner": 9,
+    "gray_banner": 8,
+    "light_gray_banner": 7,
+    "cyan_banner": 6,
+    "purple_banner": 5,
+    "blue_banner": 4,
+    "brown_banner": 3,
+    "green_banner": 2,
+    "red_banner": 1
+}