Fix catastrophic, backup deleting bug

[MaxG87]

Due to a bug in an imported component, storage_device_managers,
errors during the unmount would result in deletion of the entire
backup. This is a serious issue for a backup tool!

This branch first establishes a test that covers the wrong
behaviour. Then the erroneous component is updated, which fixes the bug.

[Copilot]

Pull request overview

This PR addresses a critical data-loss scenario by pinning/updating the storage-device-managers dependency to a fixed version and adding a regression test to ensure unmount failures do not delete backup contents.

Changes:

• Add a regression test that simulates an unmount failure and verifies backups are not deleted and the device can still be closed.
• Bump runtime/dev dependencies (notably storage-device-managers, shell-interface, typer) and update uv.lock accordingly.
• Update Docker/CI tooling to use a newer uv version and add YAML document headers to workflows/config.

Reviewed changes

Copilot reviewed 12 out of 13 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
uv.lock	Updates locked dependency set to match bumped runtime/dev requirements (incl. storage-device-managers>=1.0.1, pytest-mock).
pyproject.toml	Bumps runtime/dev dependency minimums and adds pytest-mock for the new regression test.
tests/test_cli.py	Adds regression test covering the unmount-error/backup-deletion scenario.
tests/conftest.py	Tightens fixture typing annotations (and imports typing as t).
dockerfiles/python3.10	Updates pinned uv version used in Docker test environment.
dockerfiles/python3.11	Updates pinned uv version used in Docker test environment.
dockerfiles/python3.12	Updates pinned uv version used in Docker test environment.
dockerfiles/python3.13	Updates pinned uv version used in Docker test environment.
dockerfiles/python3.14	Updates pinned uv version used in Docker test environment.
.github/workflows/python-ci.yml	Pins CI install of uv to 0.10.12 and adds YAML document marker.
.github/workflows/python-publish.yml	Adds YAML document marker (but still pins an older uv, see comment).
.github/workflows/release-please.yml	Adds YAML document marker.
.github/dependabot.yml	Adds YAML document marker.

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