fix: improve error handling in embeddings and messages

Enhance error reporting by preserving original error message when embedding
requests fail instead of generic error. Clean up error message format by
removing all file:line prefixes for better readability.

Author: deathbeam

lua/CopilotChat/client.lua

@@ -772,6 +772,7 @@ function Client:embed(inputs, model)
   while #to_process > 0 do
     local chunk_size = initial_chunk_size -- Reset chunk size for each new batch
     local threshold = BIG_EMBED_THRESHOLD -- Reset threshold for each new batch
+    local last_error = nil
 
     -- Take next chunk
     local batch = {}
@@ -788,6 +789,7 @@ function Client:embed(inputs, model)
 
       if not ok then
         log.debug('Failed to get embeddings: ', data)
+        last_error = data
         attempts = attempts + 1
         -- If we have few items and the request failed, try reducing threshold first
         if #batch <= 5 then
@@ -820,7 +822,7 @@ function Client:embed(inputs, model)
     end
 
     if not success then
-      error('Failed to process embeddings after multiple attempts')
+      error(last_error)
     end
   end
 

lua/CopilotChat/init.lua

@@ -136,9 +136,13 @@ local function show_error(err, append_newline)
   err = err or 'Unknown error'
 
   if type(err) == 'string' then
-    local message = err:match('^[^:]+:[^:]+:(.+)') or err
-    message = message:gsub('^%s*', '')
-    err = message
+    while true do
+      local new_err = err:gsub('^[^:]+:%d+: ', '')
+      if new_err == err then
+        break
+      end
+      err = new_err
+    end
   else
     err = utils.make_string(err)
   end