feat(docs): use uv and uv.lock for RTD.

Author: tm91236

.cspell/custom_misc.txt

@@ -64,6 +64,7 @@ regulariser
 RKHS
 rngs
 RPCHOLESKY
+RTD
 sdist
 sigmas
 subseteq

.readthedocs.yaml

@@ -4,11 +4,9 @@
 version: 2
 
 build:
-  os: ubuntu-22.04
+  os: ubuntu-24.04
   tools:
-    # Note that we use 3.12 here rather than 3.13 to avoid spurious Sphinx errors
-    # about not being able to link to `pathlib._locals.Path`.
-    python: "3.12"
+    python: "3.13"
   jobs:
     # Fix LFS images. See documentation at:
     # https://docs.readthedocs.com/platform/stable/build-customization.html#support-git-lfs-large-file-storage
@@ -27,12 +25,18 @@ build:
       - ./git-lfs-3.6.1/git-lfs fetch
       # Make local files to have the real content on them
       - ./git-lfs-3.6.1/git-lfs checkout
+    pre_create_environment:
+      - asdf plugin add uv
+      - asdf install uv latest
+      - asdf global uv latest
+    create_environment:
+      - uv venv "${READTHEDOCS_VIRTUALENV_PATH}"
+    install:
+      # We use the `--frozen` option instead of `--locked`, as we want RTD to build the
+      # documentation according to the repository state, even if `uv.lock` is outdated.
+      - UV_PROJECT_ENVIRONMENT="${READTHEDOCS_VIRTUALENV_PATH}" uv sync --extra doc --no-dev --frozen
 
 sphinx:
   configuration: documentation/source/conf.py
   builder: "html"
   fail_on_warning: true
-
-python:
-   install:
-    - requirements: requirements-doc.txt