provide top level snippet completions even after the first character

Author: Techatrix

src/features/completions.zig

@@ -859,11 +859,9 @@ pub fn completionAtIndex(
     };
     const source = handle.tree.source;
 
-    // Provide `top_level_decl_data` only if `offsets.lineSliceUntilIndex(handle.tree.source, source_index).len` is
-    // 0 => Empty new line, manually triggered
-    // 1 => This is the very first char on a given line
-    const at_line_start = offsets.lineSliceUntilIndex(source, source_index).len < 2;
-    if (at_line_start) {
+    const line_until_index = offsets.lineSliceUntilIndex(source, source_index);
+
+    if (line_until_index.len == 0 or std.zig.isValidId(line_until_index)) {
         try populateSnippedCompletions(&builder, &snipped_data.top_level_decl_data);
         return .{ .isIncomplete = false, .items = builder.completions.items };
     }