fix(test): unused vars

spec/command_parsing_spec.lua

@@ -50,7 +50,7 @@ describe('cp command parsing', function()
 
     local mock_cache = {
       load = function() end,
-      get_contest_data = function(platform, contest_id)
+      get_contest_data = function()
         return {
           problems = {
             { id = 'a', name = 'Problem A' },

spec/error_boundaries_spec.lua

@@ -14,7 +14,7 @@ describe('Error boundary handling', function()
     package.loaded['cp.log'] = mock_logger
 
     package.loaded['cp.scraper'] = {
-      scrape_problem_tests = function(platform, contest_id, problem_id, callback)
+      scrape_problem_tests = function(_, contest_id, problem_id, callback)
         if contest_id == 'fail_scrape' then
           callback({
             success = false,
@@ -30,7 +30,7 @@ describe('Error boundary handling', function()
           },
         })
       end,
-      scrape_contest_metadata = function(platform, contest_id, callback)
+      scrape_contest_metadata = function(_, contest_id, callback)
         if contest_id == 'fail_scrape' then
           callback({
             success = false,

spec/picker_spec.lua

@@ -157,7 +157,7 @@ describe('cp.picker', function()
       end
 
       -- Mock vim.system to return success with problems
-      vim.system = function(cmd, opts)
+      vim.system = function()
         return {
           wait = function()
             return {