feat: create query crate

crates/tinymist-query/src/completion.rs

@@ -0,0 +1,27 @@
+use crate::prelude::*;
+
+#[derive(Debug, Clone)]
+pub struct CompletionRequest {
+    pub path: PathBuf,
+    pub position: LspPosition,
+    pub position_encoding: PositionEncoding,
+    pub explicit: bool,
+}
+
+pub fn completion(
+    world: &TypstSystemWorld,
+    doc: Option<Arc<TypstDocument>>,
+    req: CompletionRequest,
+) -> Option<CompletionResponse> {
+    let source = get_suitable_source_in_workspace(world, &req.path).ok()?;
+    let typst_offset =
+        lsp_to_typst::position_to_offset(req.position, req.position_encoding, &source);
+
+    let (typst_start_offset, completions) =
+        typst_ide::autocomplete(world, doc.as_deref(), &source, typst_offset, req.explicit)?;
+
+    let lsp_start_position =
+        typst_to_lsp::offset_to_position(typst_start_offset, req.position_encoding, &source);
+    let replace_range = LspRawRange::new(lsp_start_position, req.position);
+    Some(typst_to_lsp::completions(&completions, replace_range).into())
+}