Add native NSSpellCheck and WinSpellCheck spellchecking support

[RyeMutt]

Description

Related Issues

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  • Bug Fix: Link to an issue that includes reproduction steps and testing guidance.
  • Feature/Enhancement: Link to an issue with a write-up, rationale, and requirements.

Issue Link:

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: c38d16fe-dd45-4671-9832-fad0ae82a916

📥 Commits

Reviewing files that changed from the base of the PR and between a8483f5 and c27faac.

📒 Files selected for processing (3)

• indra/llui/llspellcheck.cpp
• indra/llui/llspellcheckengine_hunspell.cpp
• indra/llui/llspellcheckengine_win32.cpp

📝 Walkthrough

Walkthrough

The build now selects Hunspell, macOS NSSpellChecker, or Windows spell checking through CMake options and backend modules. LLSpellChecker now uses a shared engine interface, with platform-specific engine implementations and updated llui wiring for sources, links, and tests.

Changes

Spellcheck backend selection

Layer / File(s)	Summary
Build options and feature gating indra/CMakeLists.txt, indra/vcpkg.json	Adds macOS and Windows spell-check build options, conditionally enables Hunspell feature wiring, and moves hunspell into an optional vcpkg feature.
Native backend module targets indra/cmake/Copy3rdPartyLibs.cmake, indra/cmake/Hunspell.cmake, indra/cmake/NSSpellChecker.cmake, indra/cmake/WinSpellCheck.cmake	Wraps Hunspell staging/discovery in native-backend checks and adds imported CMake targets for the macOS and Windows spellcheck backends.
Engine interface and Hunspell backend indra/llui/llspellcheckengine.h, indra/llui/llspellcheckengine_hunspell.cpp	Adds the LLSpellCheckEngine interface and the Hunspell-backed implementation that loads dictionaries, checks words, and returns suggestions.
Native macOS and Windows engines indra/llui/llspellcheckengine_mac.mm, indra/llui/llspellcheckengine_win32.cpp	Adds the NSSpellChecker and Windows COM spellcheck engines, including language matching, word checks, suggestions, and installed-language queries.
llui spellcheck wiring indra/llui/CMakeLists.txt	Moves llspellcheck.cpp into a dedicated spellcheck source block, exports llspellcheckengine.h, and selects the backend source and link libraries from the active option.
LLSpellChecker engine-backed flow indra/llui/llspellcheck.h, indra/llui/llspellcheck.cpp	Replaces direct Hunspell state with LLSpellCheckEngine, rebuilds accepted words, and routes spell-check activation, checks, and suggestions through the engine.

Sequence Diagram(s)

sequenceDiagram
  participant LLSpellChecker
  participant LLSpellCheckEngine
  participant LLHunspellEngine
  participant LLNSSpellEngine
  participant LLWinSpellEngine

  LLSpellChecker->>LLSpellCheckEngine: create()
  alt USE_NSSPELLCHECKER
    LLSpellCheckEngine-->>LLSpellChecker: LLNSSpellEngine
  else USE_WINSPELLCHECK
    LLSpellCheckEngine-->>LLSpellChecker: LLWinSpellEngine
  else Hunspell
    LLSpellCheckEngine-->>LLSpellChecker: LLHunspellEngine
  end
  LLSpellChecker->>LLSpellCheckEngine: setLanguage(dict_language)
  LLSpellChecker->>LLSpellCheckEngine: checkWord(word)
  LLSpellChecker->>LLSpellCheckEngine: getSuggestions(word, suggestions)

Loading

Estimated code review effort

🎯 4 (Complex) | ⏱️ ~60 minutes

Poem

🐰 I hop through engines, light and keen,
Mac, Win, and Hunspell in between.
New words I sniff, new paths I test,
A twitchy nose approves the quest.

🚥 Pre-merge checks | ✅ 3 | ❌ 2

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description is still the template placeholder and does not describe the changes or include a real issue link.	Replace the template text with a real summary of the change, add a related issue link, and note any testing or caveats.
Docstring Coverage	⚠️ Warning	Docstring coverage is 26.32% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: adding native macOS and Windows spellchecking support.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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[coderabbitai]

Actionable comments posted: 2

🧹 Nitpick comments (1)

indra/llui/llspellcheck.cpp (1)

298-336: 📐 Maintainability & Code Quality | 🔵 Trivial | 💤 Low value

addToCustomDictionary can append duplicate words to the on-disk .dic.

addToIgnoreList dedups against mIgnoreList before writing, but addToCustomDictionary writes to the custom .dic and inserts into mAcceptedWords unconditionally. Re-adding the same word across calls/sessions grows the file with duplicates (the set dedups in memory, the file does not). A guard against re-adding already-accepted words keeps the file consistent with the ignore-list behavior.

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@indra/llui/llspellcheck.cpp` around lines 298 - 336, addToCustomDictionary
currently writes every word straight to the custom dictionary file and
mAcceptedWords without checking for existing entries, so repeated calls can
duplicate entries on disk. Update LLSpellChecker::addToCustomDictionary to
mirror the dedup behavior used in addToIgnoreList by checking whether the
lowercased word is already present in mAcceptedWords or the custom dictionary
before calling addToDictFile, then only append and signal settings when it is
new.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@indra/llui/llspellcheckengine_hunspell.cpp`:
- Around line 92-106: `LLHunspellEngine::getInstalledLanguages` currently
reports a language as installed when only the `.dic` file exists, but
`LLHunspellEngine::setLanguage` requires both `.dic` and `.aff` to successfully
create `Hunspell`. Update the availability check in `getInstalledLanguages` to
verify both files for each candidate name in both the user and app dictionary
paths, so only languages that can actually be activated are returned.

In `@indra/llui/llspellcheckengine_win32.cpp`:
- Around line 73-107: Add the same main-thread thread-affinity check used
elsewhere in LLWinSpellEngine so the constructor and destructor only run on the
main thread; update LLWinSpellEngine::LLWinSpellEngine and
LLWinSpellEngine::~LLWinSpellEngine to assert on_main_thread() before any COM
lifetime work, keeping CoInitializeEx/CoUninitialize paired on the same
apartment and making the singleton teardown path explicit.

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Nitpick comments:
In `@indra/llui/llspellcheck.cpp`:
- Around line 298-336: addToCustomDictionary currently writes every word
straight to the custom dictionary file and mAcceptedWords without checking for
existing entries, so repeated calls can duplicate entries on disk. Update
LLSpellChecker::addToCustomDictionary to mirror the dedup behavior used in
addToIgnoreList by checking whether the lowercased word is already present in
mAcceptedWords or the custom dictionary before calling addToDictFile, then only
append and signal settings when it is new.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 8a24ad1e-37f8-4dce-aa3c-867c51e978a0

📥 Commits

Reviewing files that changed from the base of the PR and between 7963260 and a8483f5.

📒 Files selected for processing (13)

• indra/CMakeLists.txt
• indra/cmake/Copy3rdPartyLibs.cmake
• indra/cmake/Hunspell.cmake
• indra/cmake/NSSpellChecker.cmake
• indra/cmake/WinSpellCheck.cmake
• indra/llui/CMakeLists.txt
• indra/llui/llspellcheck.cpp
• indra/llui/llspellcheck.h
• indra/llui/llspellcheckengine.h
• indra/llui/llspellcheckengine_hunspell.cpp
• indra/llui/llspellcheckengine_mac.mm
• indra/llui/llspellcheckengine_win32.cpp
• indra/vcpkg.json