docs: add notes to stateful pin commands (#562)

docs/tinymist/frontend/neovim.typ

@@ -47,7 +47,11 @@ vim.lsp.buf.execute_command({ command = 'tinymist.pinMain', arguments = { vim.ap
 vim.lsp.buf.execute_command({ command = 'tinymist.pinMain', arguments = { nil } })
 ```
 
-There is also a plan to support multiple-file project by workspace configuration, but I don’t know what is neovim’s way, so it needs further discussion.
+There is also a plan to support multiple-file project by workspace configuration, but I don’t know whether it is neovim’s way, so it needs further discussion.
+
+#note-box[
+  `tinymist.pinMain` is a stateful command, and tinymist doesn't remember it between sessions (closing and opening the editor).
+]
 
 == Troubleshooting
 <troubleshooting>

docs/tinymist/frontend/vscode.typ

@@ -142,6 +142,10 @@ You can pin a main file by command.
 - Use command `Typst Pin Main` (tinymist.pinMainToCurrent) to set the current file as the main file.
 - Use command `Typst Unpin Main` (tinymist.unpinMain) to unset the main file.
 
+#note-box[
+  `tinymist.pinMain` is a stateful command, and tinymist doesn't remember it between sessions (closing and opening the editor).
+]
+
 === Passing Extra CLI Arguments
 <passing-extra-cli-arguments>
 There is a *global* configuration `tinymist.typstExtraArgs` to pass extra arguments to tinymist LSP, like what you usually do with `typst-cli` CLI. For example, you can set it to `["--input=awa=1", "--input=abaaba=2", "main.typ"]` to configure `sys.inputs` and entry for compiler, which is equivalent to make LSP run like a `typst-cli` with such arguments:

docs/tinymist/mod.typ

@@ -37,3 +37,5 @@
     },
   )
 })
+
+#let note-box = pro-tip