release 2.1.0: versions, a nix-gleam build, READMEHEADmainclaude-spec-matchup-redo-fixing-3

The library's version follows the format's: 2.1.0 in dub.json,
gleam.toml and both flakes. A release is numbered major.minor.patch,
major.minor being the format and shared with the specification and the
writer, the patch the library's own.

dlang/flake.lock and gleam/flake.lock: nixpkgs forward to
26.11pre1097770, the same revision in both, as the two have been at
every commit.

README:

- the two earlier readers, sisudoc-ssp-reader and
  sisudoc-ocda-db-reader, are named as what they now are: published
  frozen, the record of readers written from the specification
  alone, their work done by ocda-read;
- the documents the checks run over are the markup document samples,
  named with their repository and the spine flags that build the
  artefacts; the claims say "every document-language of the markup
  document samples" rather than a count, which changes as the samples
  do; the same in gleam/README.md, which also describes the nix-gleam
  build and names the specification's documents as .md, as they are;
- "one implementation per language", where it said "one reader";
- the reader's modes that describe the document say the same of every
  form; --languages and --files describe the file, and say so;
- a short section on building, a link to the specification, the
  format as 2.1, and the license.

Checked: D and Gleam build; with the writer at the same point, over
the markup document samples: the four dumps (D and Gleam, .ssp and
.ocda.db) identical for every document-language of the markup document
samples, ocda-read the same from every form and in both languages, and
D == Gleam in all five formats.

(assisted by Claude-Code)

1 files changed, 4 insertions, 4 deletions

diff --git a/dlang/flake.lock b/dlang/flake.lock
index 12c4c3b..ff026a4 100644
--- a/dlang/flake.lock
+++ b/dlang/flake.lock
@@ -2,11 +2,11 @@
   "nodes": {
     "nixpkgs": {
       "locked": {
-        "lastModified": 1790652569,
-        "narHash": "sha256-k8Fu4c9Z+4Nh7mUr0cfw++ITQiyEhlWxoJBOkI3tOcQ=",
-        "rev": "b6c8664de9b6cc07fe5666a29f91884ba81197c4",
+        "lastModified": 1792506237,
+        "narHash": "sha256-hVMDyAXU0kxRuG3GygbZkzf5x+aBNEC0NYEJ6KwHtD4=",
+        "rev": "5adc50831c259f87faeb09ddf930d43597197473",
         "type": "tarball",
-        "url": "https://releases.nixos.org/nixpkgs/nixpkgs-26.11pre1082290.b6c8664de9b6/nixexprs.tar.zst"
+        "url": "https://releases.nixos.org/nixpkgs/nixpkgs-26.11pre1097770.5adc50831c25/nixexprs.tar.zst"
       },
       "original": {
         "type": "tarball",