[docs] Use discord redirect (#1227)

Author: oliviertassinari

.github/ISSUE_TEMPLATE/3.get-help.md

@@ -7,4 +7,4 @@ about: 'Ask a question.'
 
 ## Ask a question
 
-Before opening an issue, please consider starting a [GitHub Discussion](https://github.com/mui/base-ui/discussions) or asking the community for help in our [Discord](https://discord.com/channels/1287292451308048406/1287292451308048409).
+Before opening an issue, please consider starting a [GitHub Discussion](https://github.com/mui/base-ui/discussions) or asking the community for help in our [Discord](https://base-ui.com/r/discord).

docs/public/_redirects

@@ -3,6 +3,9 @@
 /inbox* / 301
 /trash / 301
 
+# For links that we can't edit later on, for example hosted in the code published on npm
+/r/discord https://discord.com/invite/g6C3hUtuxz 302
+
 # Legacy redirection
 # Added in chronological order (the last line is the most recent one)
 # To be removed 3+ years after being introduced

docs/src/app/(public)/(content)/react/overview/about/page.mdx

@@ -46,7 +46,7 @@ If you want to file a bug report or contribute, visit our [GitHub](https://githu
 
 ### Discord
 
-For community support, questions, and tips, join our [Discord](https://discord.gg/g6C3hUtuxz).
+For community support, questions, and tips, join our [Discord](https://base-ui.com/r/discord).
 
 ### X