Fix depth detection and respect formatting config

[JesseHerrick]

Note

Medium Risk
Touches core Elixir parsing used for alias scoping, reference extraction, and folding ranges, so subtle depth-detection regressions could affect navigation features. Disabling WillSaveWaitUntil reduces behavior on save but is straightforward and covered by updated tests.

Overview
Fixes Elixir scope/depth tracking by switching module-stack popping from indent-based heuristics to block depth counting that understands both do..end and multi-line fn..end, while ignoring false do/end tokens in comments, strings, and heredocs via new helpers like CheckHeredoc, StripCommentsAndStrings, IsEnd, and OpensBlock.

Updates LSP features to use the same stripped-token logic for alias scoping (ExtractAliasesInScope) and folding range detection, and disables WillSaveWaitUntil formatting (capability flag off and handler returns nil), leaving formatting to textDocument/formatting. Adds regression tests for fn blocks, heredocs, and trailing fn patterns, and updates the server test to expect no edits on will-save.

^{Reviewed by Cursor Bugbot for commit a599cf7. Bugbot is set up for automated code reviews on this repo. Configure here.}

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, have a team admin enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit cd0162e. Configure here.}