Editor support generalized: shared core, language server, Vim and VS Code (from dev eb5baf9cbe59)

doc/edit/ now holds a shared Python implementation of the language's
structural layer (klammertext_edit.py) and a dependency-free language
server (klammertext_ls.py), with integrations for Emacs, Sublime Text,
Vim, and Visual Studio Code.  The editor test suite in tst/ covers the
core's API and CLI, the language server protocol, the VS Code
extension, headless Vim, and Emacs byte-equality.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

doc/edit/vim/README.md

@@ -0,0 +1,117 @@
+# Klammertext support for Vim
+
+Vim support for editing Klammertext files (`.kt` documents and `.k` klammer
+definitions): syntax highlighting, delimiter matching and jumping, structural
+reindentation, table alignment, and a delimiter checker.
+
+The structure-aware features are thin wrappers around the **shared editor
+core** (`klammertext_edit.py`) — the single Python implementation of
+Klammertext's structural layer used by the Sublime Text and VS Code
+integrations and by the Klammertext language server.  The Vim plugin runs it
+through `python3`; there is no Vim-specific reimplementation to drift out of
+sync.
+
+## Requirements
+
+- Vim 8+ (or Neovim) with `+eval` — any normal Vim; only `vim-tiny` lacks it.
+- `python3` on `PATH` (Klammertext itself already requires Python).
+- The shared core, found automatically in this order:
+  1. `g:klammertext_edit_py`, if you set it (a full path to
+     `klammertext_edit.py`);
+  2. a `klammertext_edit.py` vendored at this plugin's root (the layout the
+     Klammertext editing zip ships);
+  3. `../shared/klammertext_edit.py` relative to the plugin directory (the
+     layout of the Klammertext repository — using the plugin straight from a
+     checkout just works);
+  4. `$KLAMMERTEXT_HOME/doc/edit/shared/klammertext_edit.py`.
+
+## Install
+
+Copy (or symlink) this `vim/` directory into a Vim native package path,
+renaming it as you like:
+
+    mkdir -p ~/.vim/pack/klammertext/start
+    cp -R vim ~/.vim/pack/klammertext/start/klammertext
+
+(Neovim: `~/.local/share/nvim/site/pack/klammertext/start/klammertext`.)
+If you copy the directory out of the Klammertext tree, also copy
+`shared/klammertext_edit.py` into the copied folder's root — or set
+`g:klammertext_edit_py`.  The editing zip from the Klammertext website ships
+the vendored copy already in place.
+
+`.kt` and `.k` files then get the `klammertext` filetype.  **Note:** `.kt`
+is also Kotlin's extension, and stock Vim maps it to Kotlin; this plugin's
+`ftdetect` overrides that unconditionally.  If you edit both languages, see
+the comment in `ftdetect/klammertext.vim`.
+
+## What you get
+
+**Syntax highlighting** — the same token classes and palette as the Emacs
+and Sublime Text support: text removal (`#`, `##`, nestable `#[ ... ]#`),
+the three `@`-tiers — application (`@`, blue), definition (`@@`, green),
+system (`@@@`, orange) — each as an opening (`@name`) or a close (`name@`,
+bare `@`), opens bright and closes the same hue darker; `^`-escapes;
+verbatim `@code ... code@` interiors.  All groups are `hi def` — override
+them with `:highlight` in your vimrc.
+
+**Commands** (buffer-local; default mappings below):
+
+| Command | Does |
+|---|---|
+| `:[range]KlammertextReindent` | reindent the range (default: whole buffer) |
+| `:KlammertextAlign` | align the `@table` enclosing the cursor |
+| `:KlammertextJumpToMatch` | jump between a klammer application's opening and closing delimiter |
+| `:KlammertextCheck` | list unclosed/mismatched delimiters in the location list |
+
+Default mappings (buffer-local; suppress them all with
+`let g:klammertext_no_mappings = 1`): `<LocalLeader>i` reindents the current
+line (in visual mode, the selection), `<LocalLeader>a` aligns the enclosing
+table, `<LocalLeader>j` jumps to the matching delimiter.  `LocalLeader`
+defaults to backslash; set `maplocalleader` to taste.
+
+Reindentation is **explicit-only**: whitespace is content in Klammertext,
+so nothing reformats as a side effect of typing (`indentkeys` is emptied).
+Alignment follows the shared rules: rows end with `||`; a row with a cell
+over 30 characters or spanning lines is left untouched; beyond 100 columns
+the command declines; bars inside a nested klammer are not separators; no
+whitespace is ever inserted inside a bar run.
+
+**With `+python3`** (check `:echo has('python3')`) the shared core also runs
+in-process: the `=` operator reindents through `'indentexpr'` (`==`, `gg=G`),
+and the matching delimiter is highlighted live as the cursor sits on one —
+the show-paren equivalent, with a mismatched or unbalanced delimiter shown
+in red plus a message.  Without `+python3` the commands above still work;
+they shell out to `python3`.
+
+**Comment toggling** — `'commentstring'` is set to `# %s`, so Vim 9.1's
+built-in commenting and Neovim's `gcc`/`gc` (or the commentary plugin)
+toggle `#` line removal.
+
+## Configuration
+
+| Variable | Meaning (default) |
+|---|---|
+| `g:klammertext_edit_py` | full path to `klammertext_edit.py` (auto-detected) |
+| `g:klammertext_python` | Python interpreter (`python3`) |
+| `g:klammertext_no_mappings` | set to define no default mappings |
+
+## Neovim and the language server
+
+Neovim users can additionally attach Neovim's built-in LSP client to the
+Klammertext language server (`klammertext_ls.py`, next to the shared core)
+for diagnostics as you type, `gq`/format-document reindentation, and
+cursor-hold match highlighting:
+
+```lua
+vim.api.nvim_create_autocmd('FileType', {
+  pattern = 'klammertext',
+  callback = function()
+    vim.lsp.start {
+      name = 'klammertext-ls',
+      cmd = { 'python3', '/path/to/doc/edit/shared/klammertext_ls.py' },
+    }
+  end,
+})
+```
+
+The plugin's own commands work the same with or without it.