fix: don't refetch crate with incorrect crate name case

lua/crates/state.lua

@@ -5,7 +5,6 @@
 ---@field search_cache SearchCache
 ---@field visible boolean
 local State = {
-    api_cache = {},
     buf_cache = {},
     search_cache = {
         results = {},
@@ -14,6 +13,35 @@ local State = {
     visible = true,
 }
 
+---@param name string
+---@return string
+local function normalize_crate_name(name)
+    return name:lower():gsub("-", "_")
+end
+
+local ApiCache = {}
+
+function ApiCache.new()
+    return setmetatable({}, ApiCache)
+end
+
+function ApiCache:__index(key)
+    local val = rawget(self, key)
+    if val then
+        return val
+    end
+
+    local id = normalize_crate_name(key)
+    return rawget(self, id)
+end
+
+function ApiCache:__newindex(key, value)
+    local id = normalize_crate_name(key)
+    return rawset(self, id, value)
+end
+
+State.api_cache = ApiCache.new()
+
 ---@class BufCache
 ---@field crates table<string,TomlCrate>
 ---@field info table<string,CrateInfo>