chore: Prepare for nvim-treesitter 1.0 breaking changes

## Overview

nvim-treesitter 1.0 is coming with breaking changes. See [roadmap issue #4767](https://github.com/nvim-treesitter/nvim-treesitter/issues/4767).

## Breaking Changes Affecting This Config

### Modules Being Removed

- [ ] **`incremental_selection`** (`lua/plugins/treesitter.lua:50-58`)
- Currently using `` for node selection
- Replace with textobjects or separate plugin

- [ ] **`indent`** (`lua/plugins/treesitter.lua:47-49`)
- Moving to Neovim core
- May need adjustment when 0.11 releases

### Already Compatible

- ✅ `nvim-treesitter-textobjects` on `main` branch with standalone setup

### Query Files to Review

- [ ] `queries/yaml/highlights.scm` - `@string.special` may change to Helix-style captures
- [ ] `queries/jsx/textobjects.scm` - verify custom captures still work
- [ ] `queries/tsx/textobjects.scm` - verify custom captures still work
- [ ] `queries/typescript/folds.scm` - `@fold` should remain compatible
- [ ] `queries/typescriptreact/folds.scm` - `@fold` should remain compatible

## Timeline

- New `main` branch targets Neovim nightly only
- After Neovim 0.11 (wasm support), `main` becomes default
- Current `master` remains frozen for backwards compatibility

## Resources

- [nvim-treesitter 1.0 Roadmap](https://github.com/nvim-treesitter/nvim-treesitter/issues/4767)
- [Helix captures reference](https://docs.helix-editor.dev/themes.html#syntax-highlighting)