Backport changes from 2.3 release to 2.4 (#2799)

* Add back accidentally removed lemmas (Issue2788 #2794))

* opposite of a `Ring` [clean version of pr #1900] (#1910)

* punchOut preserves ordering (#1913)

* Wellfounded proof for sum relations (#1920)

* last revert undone by hand

* Remove extra line in CHANGELOG

* Update CHANGELOG.md

Co-authored-by: jamesmckinna <31931406+jamesmckinna@users.noreply.github.com>

* Update CHANGELOG.md

Co-authored-by: jamesmckinna <31931406+jamesmckinna@users.noreply.github.com>

* Update CHANGELOG.md

Co-authored-by: jamesmckinna <31931406+jamesmckinna@users.noreply.github.com>

* Update CHANGELOG.md

This was indeed anachronistic from 2.0

Co-authored-by: jamesmckinna <31931406+jamesmckinna@users.noreply.github.com>

* Update CHANGELOG.md

Co-authored-by: jamesmckinna <31931406+jamesmckinna@users.noreply.github.com>

* resolve issues pointed out by James.

* Update CHANGELOG.md

Co-authored-by: jamesmckinna <31931406+jamesmckinna@users.noreply.github.com>

* remove now obsolete comment

* last mistake in CHANGELOG, hopefully fixed now.

---------

Co-authored-by: jamesmckinna <31931406+jamesmckinna@users.noreply.github.com>
Co-authored-by: Nathan van Doorn <nvd1234@gmail.com>
Co-authored-by: Alice Laroche <60161310+Seiryn21@users.noreply.github.com>
Co-authored-by: matthewdaggitt <matthewdaggitt@gmail.com>

* Bring v2.3 release changes accross

* Fix typo

* Fix whitespace

---------

Co-authored-by: Jacques Carette <carette@mcmaster.ca>
Co-authored-by: jamesmckinna <31931406+jamesmckinna@users.noreply.github.com>
Co-authored-by: Nathan van Doorn <nvd1234@gmail.com>
Co-authored-by: Alice Laroche <60161310+Seiryn21@users.noreply.github.com>

Author: 5 people

CHANGELOG/v2.3.md

@@ -3,6 +3,6 @@ message: "If you use this software, please cite it as below."
 authors:
 - name: "The Agda Community"
 title: "Agda Standard Library"
-version: 2.1.1
-date-released: 2024-09-07
+version: 2.3.0
+date-released: 2025-08-02
 url: "https://github.com/agda/agda-stdlib"

CITATION.cff

@@ -2,8 +2,6 @@
 
 [![Ubuntu build](https://github.com/agda/agda-stdlib/actions/workflows/ci-ubuntu.yml/badge.svg?branch=experimental)](https://github.com/agda/agda-stdlib/actions/workflows/ci-ubuntu.yml)
 
-**Note**: The library is currently tracking Agda 2.8.0 release candidate 3 in preparation for the release of Agda 2.8.0 and version 2.3 of the library. You will need to have the release candidate installed in order to type-check it.
-
 The Agda standard library
 =========================
 

README.md

@@ -3,19 +3,19 @@ Installation instructions
 
 Note: the full story on installing Agda libraries can be found at [readthedocs](http://agda.readthedocs.io/en/latest/tools/package-system.html).
 
-Use version v2.2 of the standard library with Agda v2.7.0 or v2.7.0.1. You can find the correct version of the library to use for different Agda versions on the [Agda Wiki](https://wiki.portal.chalmers.se/agda/Libraries/StandardLibrary).
+Use version v2.3 of the standard library with Agda v2.8.0 or v2.7.0.1. You can find the correct version of the library to use for different Agda versions on the [Agda Wiki](https://wiki.portal.chalmers.se/agda/Libraries/StandardLibrary).
 
 1. Navigate to a suitable directory `$HERE` (replace appropriately) where
    you would like to install the library.
 
-2. Download the tarball of v2.2 of the standard library. This can either be
+2. Download the tarball of v2.3 of the standard library. This can either be
    done manually by visiting the Github repository for the library, or via the
    command line as follows:
    ```
-   wget -O agda-stdlib.tar.gz https://github.com/agda/agda-stdlib/archive/v2.2.tar.gz
+   wget -O agda-stdlib.tar.gz https://github.com/agda/agda-stdlib/archive/v2.3.tar.gz
    ```
    Note that you can replace `wget` with other popular tools such as `curl` and that
-   you can replace `2.2` with any other version of the library you desire.
+   you can replace `2.3` with any other version of the library you desire.
 
 3. Extract the standard library from the tarball. Again this can either be
    done manually or via the command line as follows:
@@ -26,7 +26,7 @@ Use version v2.2 of the standard library with Agda v2.7.0 or v2.7.0.1. You can f
 4. [ OPTIONAL ] If using [cabal](https://www.haskell.org/cabal/) then run
    the commands to install via cabal:
    ```
-   cd agda-stdlib-2.2
+   cd agda-stdlib-2.3
    cabal install
    ```
 
@@ -42,7 +42,7 @@ Use version v2.2 of the standard library with Agda v2.7.0 or v2.7.0.1. You can f
 6. Register the standard library with Agda's package system by adding
    the following line to `$AGDA_DIR/libraries`:
    ```
-   $HERE/agda-stdlib-2.2/standard-library.agda-lib
+   $HERE/agda-stdlib-2.3/standard-library.agda-lib
    ```
 
 Now, the standard library is ready to be used either: