fix(website): cross-locale doc links + drop empty ko locale (#31895)

The locale switcher appeared broken because hardcoded markdown links
(`](/docs/X)`) got double-prefixed by Docusaurus to `/docs/<locale>/docs/X`
(404) in non-English locales, and the MDX hero `<a href>` on the index
page escaped locale routing entirely.

Changes:
- Rewrite 922 `](/docs/X)` -> `](/X)` across 166 docs files (strip trailing
  .md too). Docusaurus prepends locale + baseUrl itself.
- docs/index.md -> index.mdx; hero "Get Started" anchor -> Docusaurus
  <Link> so it stays inside the active locale.
- Drop `ko` locale entirely from docusaurus.config.ts + delete i18n/ko/
  (4 stale auto-translated kanban pages, <2% coverage, misleading).

Verified `npm run build` succeeds for both en and zh-Hans; `build/zh-Hans/
index.html` has no /docs/zh-Hans/docs/... double-prefixed paths.

PR2 will translate the 335 English docs into i18n/zh-Hans/.

website/docs/user-guide/messaging/teams.md

@@ -8,7 +8,7 @@ description: "Set up Hermes Agent as a Microsoft Teams bot"
 
 Connect Hermes Agent to Microsoft Teams as a bot. Unlike Slack's Socket Mode, Teams delivers messages by calling a **public HTTPS webhook**, so your instance needs a publicly reachable endpoint — either a dev tunnel (local dev) or a real domain (production).
 
-Need meeting summaries from Microsoft Graph events rather than normal bot conversations? Use the dedicated setup page: [Teams Meetings](/docs/user-guide/messaging/teams-meetings).
+Need meeting summaries from Microsoft Graph events rather than normal bot conversations? Use the dedicated setup page: [Teams Meetings](/user-guide/messaging/teams-meetings).
 
 ## How the Bot Responds
 
@@ -168,7 +168,7 @@ Clicking a button resolves the approval inline and replaces the card with the de
 
 ### Meeting Summary Delivery (Teams Meeting Pipeline)
 
-When the [Teams meeting pipeline plugin](/docs/user-guide/messaging/msgraph-webhook) is enabled, this adapter also handles outbound delivery of meeting summaries — one Teams integration surface, not two. After a meeting's transcript is summarized, the writer posts the summary into your chosen Teams target.
+When the [Teams meeting pipeline plugin](/user-guide/messaging/msgraph-webhook) is enabled, this adapter also handles outbound delivery of meeting summaries — one Teams integration surface, not two. After a meeting's transcript is summarized, the writer posts the summary into your chosen Teams target.
 
 Pipeline summary delivery is configured under the `teams` platform entry alongside the bot config:
 
@@ -193,7 +193,7 @@ platforms:
 | Mode | Use when | Trade-off |
 |------|----------|-----------|
 | `incoming_webhook` | Simple "post a summary into this channel" with a static Teams-generated URL. | No reply threading, no reactions, shows as the webhook's configured identity. |
-| `graph` | Threaded channel posts or 1:1/group chat posts under the bot's identity via Microsoft Graph. | Requires the [Graph app registration](/docs/guides/microsoft-graph-app-registration) with `ChannelMessage.Send` (channel) or `Chat.ReadWrite.All` (chat) application permissions. |
+| `graph` | Threaded channel posts or 1:1/group chat posts under the bot's identity via Microsoft Graph. | Requires the [Graph app registration](/guides/microsoft-graph-app-registration) with `ChannelMessage.Send` (channel) or `Chat.ReadWrite.All` (chat) application permissions. |
 
 If the `teams_pipeline` plugin is **not** enabled, these settings are inert — they only wire up when the pipeline runtime binds to the Graph webhook ingress.
 
@@ -248,5 +248,5 @@ Treat `TEAMS_CLIENT_SECRET` like a password — rotate it periodically via the A
 
 ## Related Docs
 
-- [Teams Meetings](/docs/user-guide/messaging/teams-meetings)
-- [Operate the Teams Meeting Pipeline](/docs/guides/operate-teams-meeting-pipeline)
+- [Teams Meetings](/user-guide/messaging/teams-meetings)
+- [Operate the Teams Meeting Pipeline](/guides/operate-teams-meeting-pipeline)