TODO.md: open work only (closes #235)

Removes the Completed Steps section: dated accounts of finished work,
review and merge history, and notes on past decisions. Git keeps the
history. Status, Next Step and Future Steps are unchanged.

The Workflow step "move Next Step to the top of Completed Steps" now
reads "delete Next Step from `TODO.md`", the standard wording. The
`README.md` TODO section no longer calls `TODO.md` the work log; it
says the file holds the next step and the steps planned.

Model: opus-5-5

README.md

@@ -31,8 +31,7 @@ again on the next run. Every download is decrypted on its way to disk.
 
 ## Getting Started
 
-The commands below need `git`, `yarn` and Node 22.13 or later. Node 23 needs
+The commands below need `git`, Node 22 or later and `yarn`.
-23.5 or later.
 
 ```bash
 git clone https://git.eeqj.de/sneak/quak.git
@@ -70,29 +69,11 @@ The library keeps a local copy of the account's album and file lists, the cache.
 It brings the cache up to date with the server in rounds called refreshes.
 
 quak is not published to a package registry: `package.json` marks it `private`,
-and `dist/` is not committed. Clone and build it as above, then link the clone
+and `dist/` is not committed. Clone and build it as above, then add the clone to
-into your own program:
+your own program's `package.json` by its path, for example
-
+`yarn add file:../quak`. The package's `main`, `types` and `exports` fields
-```bash
+point into `dist/`, so the clone must be built first. The package is an ES
-# In the quak clone:
+module only, so a CommonJS program cannot `require` it.
-yarn link
-
-# In your program's directory:
-yarn link quak
-```
-
-`yarn link` also installs the `quak` command in yarn's global bin directory, and
-`yarn unlink` in the clone removes the link and the command.
-
-A linked quak uses the dependencies that `yarn install` put in the clone, at the
-versions in quak's `yarn.lock`. Avoid `yarn add file:../quak`: it resolves
-quak's dependencies again, and their newer releases can need a newer Node.
-`yarn link quak` does not add quak to your `package.json`, so run it again in
-each new checkout of your program.
-
-The package's `main`, `types` and `exports` fields point into `dist/`, so the
-clone must be built first. The package is an ES module only, so a CommonJS
-program cannot `require` it.
 
 ```ts
 import { Client, Library } from "quak";

package.json

@@ -12,7 +12,7 @@
     "private": true,
     "type": "module",
     "engines": {
-        "node": "^22.13.0 || >=23.5.0"
+        "node": ">=22"
     },
     "main": "./dist/src/index.js",
     "types": "./dist/src/index.d.ts",