several scripts: let uv see the project before syncing it | refactor some scripts that use uv (#17436)

* Let uv see the project before syncing it

uv refuses to run when a project pins a required-version it does not
match, in either direction: RomM pins ==0.12.13, which fails against
both the 0.10.3 a container was built with and the 0.12.17 latest
installs.

UV_PROJECT_DIR points setup_uv at the project so it reads that pin. It
is a prefix like PYTHON_VERSION and UV_VERSION, and the call sits
directly under fetch_and_deploy: the project is on disk by then, and
the deploy has closed its message block, which setup_uv needs since it
opens one of its own. That is also the only call needed - nothing
between the old early call and the deploy uses uv or Python, so the two
collapse into one.

Two things found along the way:

UV_PYTHON was set as a command prefix on setup_uv in 14 places. setup_uv
reads PYTHON_VERSION, never UV_PYTHON, and a prefix assignment does not
outlive the call, so those pins did nothing. They now use
PYTHON_VERSION, which installs the interpreter they were asking for.

Five update scripts had no setup_uv at all while their install
counterpart pinned a Python version. They now carry the same pin.

immich is left out: it runs uv through sudo -u inside a retry loop.

* yubal: drop the uv 0.7.19 pin

The pin came in with the script and was never explained. uv 0.7.19 is
from 2025-07-02; yubal's uv.lock has carried revision 3 since at least
2025-12-27, and older uv refuses a newer lockfile revision. The script
runs uv sync --frozen, so there is no fallback.

yubal declares no required-version of its own, so latest is what it
gets - and if it ever pins one, that pin is now honoured.

ct/flatnotes.sh

@@ -38,10 +38,10 @@ function update_script() {
 
     create_backup /opt/flatnotes/.env /opt/flatnotes/data
 
-    PYTHON_VERSION="3.13" setup_uv
     NODE_VERSION="24" setup_nodejs
 
     CLEAN_INSTALL=1 fetch_and_deploy_gh_release "flatnotes" "dullage/flatnotes" "tarball"
+    PYTHON_VERSION="3.13" UV_PROJECT_DIR="/opt/flatnotes" setup_uv
 
     restore_backup