Move biome definitions to YAML configuration with hot reload support (#404)

* Biomes can now be defined in the world configuration and loaded dynamically

- Enabling biome definitions outsite of code
- Biomes reload in the same way as items

* Added hot reload to biomes

"reload biomes" will now hot reload changes, like on items.

* Fixed review comments and minor other improvements

1. YAML tags changed to lowercase

  - Changed yaml:"darkArea" to yaml:"darkarea"
  - Changed yaml:"litArea" to yaml:"litarea"
  - Changed yaml:"requiredItemId" to yaml:"requireditemid"
  - Changed yaml:"usesItem" to yaml:"usesitem"
  - All YAML tags now follow the lowercase convention as requested

2. Implemented Loadable interface methods

  - Added Id() method that returns the biome ID as a string
  - Added Validate() method with proper validation logic
  - Added Filepath() method that returns the individual file path
  - BiomeInfo now satisfies the Loadable[string] interface

3. Refactored to use fileloader.LoadAllFlatFiles pattern

  - Converted from single biomes.yaml file to individual biome files
(e.g., city.yaml, forest.yaml)
  - Changed loading mechanism to use fileloader.LoadAllFlatFiles[string,
*BiomeInfo]()
  - Created individual biome files in _datafiles/world/default/biomes/
directory

I looked at races/mobs/items and tried to follow the same pattern.

Additional fixes and changes:

  - Updated all references to BiomeInfo fields to use the new exported
fields
  - Fixed method calls from Symbol() to GetSymbol() and Name() to Name
field access
  - Fixed the return type of GetBiome() to return *BiomeInfo instead of
BiomeInfo
Also had to fix an unreachable code issue in mutators.go (This was a
compiler error due to unreachable code after line 49 because of a
'return false') This may be intentional, but the compiler will not make
the binary without this change.

* Added two missing hard coded biomes

Added missing hard coded biomes as regular biome files:
  - Land
  - Dungeon

Also added them back as hard coded fallbacks in biomes.go

* Fixed a slight duplication issue with the Dungeon biome

* Simplified biome system and removed ValidateBiomes function

- Removed all hardcoded biomes from biomes.go
  - Replaced with single default fallback biome when no files are loaded
  - Removed ValidateBiomes() function and its call from main.go
  - Changed GetAllBiomes() to return []BiomeInfo instead of []*BiomeInfo
to prevent accidental modifications
  - Reverted mutators.go changes that were accidentally included in this
branch

* Cleaned up old single biomes.yaml in /default and added all the individual biomes to /empty

* Fixed biome-related nil pointer panics and improved error handling

- Added defensive nil checks in mapper.go before calling biome methods
  - Ensured default biome always exists after LoadBiomeDataFiles() is
called
  - Added warning log when a requested biome is not found, showing biome
name, room ID, and zone
  - Improved biome fallback logic to prevent nil pointer dereferences
  - Added mudlog import to rooms.go for biome warning messages

* Added startup biome validation and improved missing biome handling

- Added validateRoomBiomes() function in mapper that checks all rooms
during PreCacheMaps()
  - Logs warnings at startup for rooms without biomes (when zone also
has no default)
  - Logs warnings for rooms referencing non-existent biomes
  - Provides summary count of missing and invalid biome references

* Removed empty line in main.go

Author: MorquinDevlar

_datafiles/world/default/biomes/cave.yaml

@@ -0,0 +1,9 @@
+biomeid: cave
+name: Cave
+symbol: ⌬
+description: Dark areas underground.
+darkarea: true
+litarea: false
+requireditemid: 0
+usesitem: false
+burns: false

_datafiles/world/default/biomes/city.yaml

@@ -0,0 +1,11 @@
+biomeid: city
+name: City
+symbol: •
+description: Cities are generally well protected. Law enforcement will attempt to
+  subdue those who murder or steal. It's generally considered a safe area although
+  it's not unknown for predators to hunt within their walls.
+darkarea: false
+litarea: true
+requireditemid: 0
+usesitem: false
+burns: false

_datafiles/world/default/biomes/cliffs.yaml

@@ -0,0 +1,9 @@
+biomeid: cliffs
+name: Cliffs
+symbol: ▼
+description: Steep, rocky areas that can be dangerous to navigate.
+darkarea: false
+litarea: false
+requireditemid: 0
+usesitem: false
+burns: false

_datafiles/world/default/biomes/desert.yaml

@@ -0,0 +1,9 @@
+biomeid: desert
+name: Desert
+symbol: '*'
+description: Harsh and dry.
+darkarea: false
+litarea: false
+requireditemid: 0
+usesitem: false
+burns: false

_datafiles/world/default/biomes/dungeon.yaml

@@ -0,0 +1,9 @@
+biomeid: dungeon
+name: Dungeon
+symbol: •
+description: These are cave-like underground areas built with a purpose.
+darkarea: true
+litarea: false
+requireditemid: 0
+usesitem: false
+burns: false

_datafiles/world/default/biomes/farmland.yaml

@@ -0,0 +1,9 @@
+biomeid: farmland
+name: Farmland
+symbol: ','
+description: Cultivated land used for growing crops.
+darkarea: false
+litarea: false
+requireditemid: 0
+usesitem: false
+burns: true

_datafiles/world/default/biomes/forest.yaml

@@ -0,0 +1,10 @@
+biomeid: forest
+name: Forest
+symbol: ♣
+description: Forests are generally green and verdant. All types of creatures lurk
+  within them. Plenty of trees.
+darkarea: false
+litarea: false
+requireditemid: 0
+usesitem: false
+burns: true

_datafiles/world/default/biomes/fort.yaml

@@ -0,0 +1,9 @@
+biomeid: fort
+name: Fort
+symbol: •
+description: Forts are cities or dwellings that are fortified.
+darkarea: false
+litarea: true
+requireditemid: 0
+usesitem: false
+burns: false

_datafiles/world/default/biomes/house.yaml

@@ -0,0 +1,9 @@
+biomeid: house
+name: House
+symbol: ⌂
+description: Standard domiciles and other dwellings.
+darkarea: false
+litarea: true
+requireditemid: 0
+usesitem: false
+burns: true

_datafiles/world/default/biomes/land.yaml

@@ -0,0 +1,9 @@
+biomeid: land
+name: Land
+symbol: •
+description: The world is made of land.
+darkarea: false
+litarea: true
+requireditemid: 0
+usesitem: false
+burns: false