refactor(completion): evolve Request into Session + surface-level cleanup

lua/lsp/completion/popup.lua

@@ -1,6 +1,7 @@
 local MAX_WIDTH = 80
 local MAX_HEIGHT = 20
 local HALF_HEIGHT = math.floor(MAX_HEIGHT / 2)
+local SNIPPET_KIND = vim.lsp.protocol.CompletionItemKind.Snippet
 
 local NS = vim.api.nvim_create_namespace("ow.lsp.completion.popup")
 
@@ -28,14 +29,15 @@ end
 ---@return integer? width
 local function build_content(item, ft)
     local sections = {}
-    if item.detail then
-        table.insert(sections, fence(ft, item.detail))
-    end
-    if item.snippet then
+    if item.snippet and item.raw.kind == SNIPPET_KIND then
         table.insert(sections, fence(ft, item.snippet))
-    end
-    if item.doc then
-        table.insert(sections, item.doc)
+    else
+        if item.detail then
+            table.insert(sections, fence(ft, item.detail))
+        end
+        if item.doc then
+            table.insert(sections, item.doc)
+        end
     end
     if #sections == 0 then
         return nil, nil