refactor(credentials): promote login/logout to top-level actions (#292)

## Problem

`:CP credentials login/logout/clear` is verbose and inconsistent with
other
actions that are all top-level (`:CP run`, `:CP submit`, etc.). The
clear-all
subcommand is also unnecessary since re-logging in overwrites existing
credentials.

## Solution

Replace `:CP credentials {login,logout,clear}` with `:CP login
[platform]`
and `:CP logout [platform]`. Remove the clear-all command and the
credentials
subcommand dispatch — login/logout are now regular actions routed
through the
standard action dispatcher.

lua/cp/commands/init.lua

@@ -83,28 +83,8 @@ local function parse_command(args)
       else
         return { type = 'action', action = 'interact' }
       end
-    elseif first == 'credentials' then
-      local subcommand = args[2]
-      if not subcommand then
-        return {
-          type = 'error',
-          message = 'credentials command requires subcommand (login, logout, clear)',
-        }
-      end
-      if vim.tbl_contains({ 'login', 'logout' }, subcommand) then
-        return {
-          type = 'credentials',
-          subcommand = subcommand,
-          platform = args[3],
-        }
-      elseif subcommand == 'clear' then
-        return {
-          type = 'credentials',
-          subcommand = 'clear',
-        }
-      else
-        return { type = 'error', message = 'unknown credentials subcommand: ' .. subcommand }
-      end
+    elseif first == 'login' or first == 'logout' then
+      return { type = 'action', action = first, platform = args[2] }
     elseif first == 'stress' then
       return {
         type = 'action',
@@ -345,6 +325,10 @@ function M.handle_command(opts)
       require('cp.race').start(cmd.platform, cmd.contest, cmd.language)
     elseif cmd.action == 'race_stop' then
       require('cp.race').stop()
+    elseif cmd.action == 'login' then
+      require('cp.credentials').login(cmd.platform)
+    elseif cmd.action == 'logout' then
+      require('cp.credentials').logout(cmd.platform)
     end
   elseif cmd.type == 'problem_jump' then
     local platform = state.get_platform()
@@ -374,15 +358,6 @@ function M.handle_command(opts)
 
     local setup = require('cp.setup')
     setup.setup_contest(platform, contest_id, problem_id, cmd.language)
-  elseif cmd.type == 'credentials' then
-    local creds = require('cp.credentials')
-    if cmd.subcommand == 'login' then
-      creds.login(cmd.platform)
-    elseif cmd.subcommand == 'logout' then
-      creds.logout(cmd.platform)
-    elseif cmd.subcommand == 'clear' then
-      creds.clear()
-    end
   elseif cmd.type == 'cache' then
     local cache_commands = require('cp.commands.cache')
     cache_commands.handle_cache_command(cmd)

lua/cp/constants.lua

@@ -13,7 +13,8 @@ M.ACTIONS = {
   'race',
   'stress',
   'submit',
-  'credentials',
+  'login',
+  'logout',
 }
 
 M.PLATFORM_DISPLAY_NAMES = {

lua/cp/credentials.lua

@@ -7,10 +7,7 @@ local state = require('cp.state')
 function M.login(platform)
   platform = platform or state.get_platform()
   if not platform then
-    logger.log(
-      'No platform specified. Usage: :CP credentials login <platform>',
-      vim.log.levels.ERROR
-    )
+    logger.log('No platform specified. Usage: :CP login <platform>', vim.log.levels.ERROR)
     return
   end
 
@@ -35,10 +32,7 @@ end
 function M.logout(platform)
   platform = platform or state.get_platform()
   if not platform then
-    logger.log(
-      'No platform specified. Usage: :CP credentials logout <platform>',
-      vim.log.levels.ERROR
-    )
+    logger.log('No platform specified. Usage: :CP logout <platform>', vim.log.levels.ERROR)
     return
   end
   cache.load()
@@ -46,10 +40,4 @@ function M.logout(platform)
   logger.log(platform .. ' credentials cleared', vim.log.levels.INFO, true)
 end
 
-function M.clear()
-  cache.load()
-  cache.clear_credentials(nil)
-  logger.log('all credentials cleared', vim.log.levels.INFO, true)
-end
-
 return M