Initial commit: Klammertext source distribution

Curated source subset assembled by klammertext-dev's doc/make_dist.sh: the Klammermachine (mac), the Standard Klammer Set (sks), the commands (com), editor plugins and install guides (doc), a test subset (tst), and lib/bin placeholders. Builds with 'make -C com'.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

sks/document/reference.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include <string>
+#include <vector>
+#include <tuple>
+#include <regex>
+#include "character.h"
+
+
+using numbered_element_spec = std::tuple<std::string, std::string, std::string>;
+//using numbered_elements = std::vector<std::vector<numbered_element_spec>>;
+using numbered_elements = std::vector<numbered_element_spec>;
+
+numbered_elements html_line_states(std::vector<std::string> lines);
+numbered_elements latex_line_states(std::vector<std::string> lines);
+
+std::pair<std::string, int> add_html_caption_numbers(std::string html_text, int& chapter_number);
+std::string add_latex_caption_numbers(std::string text);
+
+std::string resolve_caption_references(
+    std::string target, std::vector<std::string> lines, numbered_elements states);
+