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/vscode/syntaxes/klammertext.tmLanguage.json

@@ -0,0 +1,132 @@
+{
+    "//": [
+        "TextMate grammar for Klammertext — the VS Code port of",
+        "doc/edit/sublime/Klammertext.sublime-syntax (same token classes,",
+        "same scope names; see that file's header for the full rationale).",
+        "",
+        "What it highlights: text removal (#, ##, nestable #[ ... ]#,",
+        "whitespace operators left unscoped), the three @-tiers — application",
+        "(@), definition (@@), system (@@@) — each as an opening (@name, one",
+        "unit) or a close (name@, bare @), ^-escapes (consumed, unscoped),",
+        "and verbatim @code ... code@ interiors.",
+        "",
+        "How open vs. close is decided (the same rule as every integration):",
+        "a delimiter whose NAME follows the @-run is an OPENING; a bare",
+        "@-run, or one whose NAME precedes it, is a CLOSING.  The",
+        "(?![A-Za-z0-9_@]) look-ahead on every closing keeps foo@bar correct.",
+        "",
+        "SYNC: the literal-klammer set's source of truth is LITERAL_KLAMMERS",
+        "in doc/edit/shared/klammertext_edit.py.  A static grammar cannot",
+        "read it: to add a literal klammer 'foo', copy the @code begin/end",
+        "rule below with code -> foo (and mirror it in the Emacs, Sublime,",
+        "and Vim artifacts; all are seeded with just 'code').",
+        "",
+        "Delimiter matching, indentation, alignment, and diagnostics are not",
+        "tokenizer concerns — they come from the Klammertext language server",
+        "via extension.js.",
+        "",
+        "The ## rule's end pattern never matches, so the region runs to the",
+        "end of the file (## removes the rest of the file by definition)."
+    ],
+    "name": "Klammertext",
+    "scopeName": "text.klammertext",
+    "patterns": [
+        {
+            "match": "\\^."
+        },
+        {
+            "begin": "#\\[",
+            "beginCaptures": {
+                "0": { "name": "punctuation.definition.comment.klammertext" }
+            },
+            "end": "\\]#",
+            "endCaptures": {
+                "0": { "name": "punctuation.definition.comment.klammertext" }
+            },
+            "name": "comment.block.klammertext",
+            "patterns": [
+                { "include": "#removal-block" }
+            ]
+        },
+        {
+            "match": "#[-+/]\\d*"
+        },
+        {
+            "begin": "##",
+            "beginCaptures": {
+                "0": { "name": "punctuation.definition.comment.klammertext" }
+            },
+            "end": "$never^",
+            "name": "comment.block.klammertext"
+        },
+        {
+            "begin": "#",
+            "beginCaptures": {
+                "0": { "name": "punctuation.definition.comment.klammertext" }
+            },
+            "end": "$",
+            "name": "comment.line.klammertext"
+        },
+        {
+            "begin": "@code(?![A-Za-z0-9_])",
+            "beginCaptures": {
+                "0": { "name": "entity.name.function.begin.klammertext" }
+            },
+            "end": "code@",
+            "endCaptures": {
+                "0": { "name": "entity.name.function.end.klammertext" }
+            }
+        },
+        {
+            "match": "@@@[A-Za-z0-9_]+",
+            "name": "keyword.control.begin.klammertext"
+        },
+        {
+            "match": "@@@(?![A-Za-z0-9_@])",
+            "name": "keyword.control.end.klammertext"
+        },
+        {
+            "match": "[A-Za-z0-9_]+@@@(?![A-Za-z0-9_@])",
+            "name": "keyword.control.end.klammertext"
+        },
+        {
+            "match": "@@[A-Za-z0-9_]+",
+            "name": "storage.type.begin.klammertext"
+        },
+        {
+            "match": "@@(?![A-Za-z0-9_@])",
+            "name": "storage.type.end.klammertext"
+        },
+        {
+            "match": "[A-Za-z0-9_]+@@(?![A-Za-z0-9_@])",
+            "name": "storage.type.end.klammertext"
+        },
+        {
+            "match": "@[A-Za-z0-9_]+",
+            "name": "entity.name.function.begin.klammertext"
+        },
+        {
+            "match": "@(?![A-Za-z0-9_@])",
+            "name": "entity.name.function.end.klammertext"
+        },
+        {
+            "match": "[A-Za-z0-9_]+@(?![A-Za-z0-9_@])",
+            "name": "entity.name.function.end.klammertext"
+        }
+    ],
+    "repository": {
+        "removal-block": {
+            "begin": "#\\[",
+            "beginCaptures": {
+                "0": { "name": "punctuation.definition.comment.klammertext" }
+            },
+            "end": "\\]#",
+            "endCaptures": {
+                "0": { "name": "punctuation.definition.comment.klammertext" }
+            },
+            "patterns": [
+                { "include": "#removal-block" }
+            ]
+        }
+    }
+}