docs(tally): add tally to /help + website docs; translate to all locales (#1342)

- Add a 'Voice channel tally' group to /help with the three commands.
- Add a Voice Channel Tally section to the website docs (docs.ejs).
- Translate the commands.tally bot strings + help_group_tally into all 10
  other bot locales, and the new docs.* web strings into all 10 web locales.
- Fix stale need_one_input string (ign/squadron_short -> username/squadron).

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

BOT/locales/en.json

@@ -598,7 +598,8 @@
     "help_group_meta": "Meta",
     "help_group_stacks": "Stacks",
     "help_group_settings": "Settings & info",
-    "help_translate_hint": "Right-click a message → Apps to translate it"
+    "help_translate_hint": "Right-click a message → Apps to translate it",
+    "help_group_tally": "Voice channel tally"
   },
   "dev": {
     "restricted_dev_team": "This command is restricted to the dev team.",
@@ -860,7 +861,7 @@
       "status_line": "{base}: {verb} against {opponent}",
       "not_in_vc": "You must be connected to a voice channel to use this.",
       "premium_required": "This is a premium feature. Use /unlock to enable it for this server.",
-      "need_one_input": "Provide exactly one of `ign` or `squadron_short`.",
+      "need_one_input": "Provide exactly one of `username` or `squadron`.",
       "already_active": "A tally is already active in **{channel}** tracking **{target}**. Use /tally-transfer or /tally-clear first.",
       "claimed": "Now tracking **{target}** in **{channel}**. Status set to `0W-0L`.",
       "no_active": "There is no active tally in **{channel}**.",