Technician updater and one shared Python environment (v0.9.0)

update_windows.bat / update_macos.command: fetch release tags from Gitea,
move the folder to the newest vX.Y (git downloads only what changed),
connect a folder unpacked from a release zip on first run, install git/uv
when missing and sync the Python libraries. Developer copies on a branch
are left alone.

run_* and update_* share one environment (KotaTechnicianTool/venv)
instead of one per version.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

update_macos.command

@@ -0,0 +1,74 @@
+#!/bin/bash
+# KOTA Sensorbox Technician Tool - update to the newest released version.
+# Checks Gitea for the newest release tag (vX.Y) and downloads only what changed (git).
+# Works in a git clone and in a folder unpacked from a release zip (it is connected on first run).
+# If Finder refuses to open this file, run it once as:  bash update_macos.command
+cd "$(dirname "$0")" || exit 1
+
+REPO_URL="${KOTA_REPO_URL:-https://gitea.kota-app.com/kkallas/kota-technician-tool.git}"
+export UV_PROJECT_ENVIRONMENT="${UV_PROJECT_ENVIRONMENT:-$HOME/Library/Caches/KotaTechnicianTool/venv}"
+export PATH="$HOME/.local/bin:$PATH"
+
+finish() {
+    [ -z "$KOTA_NO_PAUSE" ] && [ -t 0 ] && read -r -p "Press Enter to close..." _
+    exit "$1"
+}
+fail() { echo; echo "[!] $*"; echo "[!] Update did not finish."; finish 1; }
+
+# ---- git (macOS: the Command Line Tools installer offers it) --------------
+if ! git --version >/dev/null 2>&1; then
+    if [ "$(uname)" = Darwin ]; then
+        xcode-select --install >/dev/null 2>&1
+        fail "Git is being installed (Apple Command Line Tools). Run this again when the installer has finished."
+    fi
+    fail "Git is not installed."
+fi
+
+# ---- connect a folder unpacked from a zip ----------------------------------
+if [ ! -d .git ]; then
+    echo "Connecting this folder to $REPO_URL ..."
+    git init -q && git remote add origin "$REPO_URL" || fail "Cannot set up git in this folder."
+fi
+
+# A developer copy follows a branch; it is updated with "git pull", not here.
+if git rev-parse -q --verify HEAD >/dev/null 2>&1 && branch=$(git symbolic-ref -q --short HEAD); then
+    echo "This is a developer copy on branch $branch. Update it with: git pull"
+    finish 0
+fi
+
+echo "Checking for a new version..."
+git fetch --quiet --force --tags origin ||
+    fail "Cannot reach $REPO_URL. Check the Internet connection and your Gitea login, then try again."
+
+latest=$(git tag -l 'v*' --sort=-v:refname | head -n 1)
+[ -n "$latest" ] || fail "No released version found on the server."
+current=$(git describe --tags --exact-match HEAD 2>/dev/null)
+
+if [ "$current" = "$latest" ]; then
+    echo "You already have the newest version $latest."
+else
+    if [ -n "$current" ]; then
+        if [ -n "$(git status --porcelain --untracked-files=no)" ]; then
+            echo "Some tool files in this folder were changed by hand. They will be replaced by $latest."
+            read -r -p "Continue? [y/N] " answer
+            [[ "$answer" =~ ^[Yy]$ ]] || fail "Cancelled."
+        fi
+        echo "Updating $current -> $latest. Changes:"
+        git --no-pager log --oneline --no-decorate "$current..$latest"
+    else
+        echo "Installing $latest..."
+    fi
+    git -c advice.detachedHead=false checkout -q -f "$latest" || fail "Checkout of $latest failed."
+    echo "Now on $latest."
+fi
+
+# ---- Python libraries (only what changed) ----------------------------------
+if ! command -v uv >/dev/null 2>&1; then
+    echo "Installing uv (Python package runner, current user only)..."
+    curl -LsSf https://astral.sh/uv/install.sh | sh || fail "uv installation failed. Ask the firmware team for help."
+fi
+echo "Checking Python libraries..."
+uv sync --frozen --no-dev --python 3.12 --quiet || fail "Installing Python libraries failed."
+echo
+echo "Done. Start the tool with run_macos.command."
+finish 0