kdesc --rewrite from the reflection klammerset; txt caption rules the block's width

Assembled from klammertext-dev e99530408517. The katom rewrite patterns
are rendered from ref/ (a table in dispatch order, patterns through @c),
the procedural listing having left mac/; a plain-text caption's rule is
as long as the table or listing it captions; the editor-support comments
name the tools' new dev/ location.

env/makefile.env

@@ -18,7 +18,7 @@ UNAME_S     := $(shell uname -s)
 CPP_VERSION := c++20
 # Default compiler: clang on macOS, gcc elsewhere. gcc-built Klammertext
 # binaries crash at runtime on macOS (a documented gcc/macOS codegen issue), so
-# gcc there is only a compile-time conformance check (via `./dbg/rebuild.sh
+# gcc there is only a compile-time conformance check (via `./dev/rebuild.sh
 # gcc`, which compiles under g++ then rebuilds with clang). Override with
 # `make COMPILER=...`.
 ifeq ($(UNAME_S),Darwin)