Fly's config lib

- Generic JSON config manager with typed deserialization (JsonConfigManager<T>)
- Auto-creates default config file if missing
- Hot-reload on file change detection (reloadIfChanged)
- Corrupted config auto-backup with timestamp before falling back to defaults
- Raw JsonObject access for advanced manual parsing
- In-place config modification with auto-save (modify(Consumer<T>))
- Registry lookup with caching for items, blocks, and entity types (RegistryConfigHelper)
- Handles both namespaced (mod:id) and bare (id → minecraft:id) resource locations
- NBT pattern matching on ItemStacks (NbtPatternMatcher)
- Partial NBT matching — pattern only needs to be a subset of the item's full NBT
- Exact NBT matching via = prefix on pattern string
- List matching — strict (all pattern elements must be in stack list) or non-strict (any one matches)
- Recursive compound tag matching
- Numeric type-insensitive comparison (ShortTag(2s) matches IntTag(2))
- Pattern cache to avoid re-parsing the same pattern string repeatedly
- Regex-based config key mapping with capture group support (RegexConfigHelper)
- Exact string mappings and regex: prefixed pattern mappings in the same config block
- Capture group substitution in mapped values via $1, $2, etc.