Wetterdienst

Feature
- Add logo for restapi
- [Breaking] Add dedicated unit converter

Attention: Many units are changed to be more consistent with typical meteorological units. We now use `°C` for
temperatures. Also, length units are now separated in `length_short`, `length_medium` and `length_long` to get more
reasonable decimals. Fore more information, see the new units chapter (usage/units) in the documentation.

Refactor
- Add reasonable upper bounds for dependencies

Fix
- Filter out invalid underscore prefixed files

Feature
- Add setting `ts_complete=False` that allows to prevent building a complete time series

Refactor
- Docs: Change to markdown using mkdocs
- Settings: Switch to `pydantic_settings` for settings management
- Improve wetterdienst api class
- Dissolve wetterdienst notebook into examples
- Use `duckdb.sql` and ask only for WHERE clause
- Update restapi annotations
- Use `Settings` in restapi/cli core functions
- Restapi/Cli: Use pydantic models for request parameters
- Rename `dropna` to `drop_nulls`
- Change default of `drop_nulls` to True
- Replace occurrences of `dt.timezone.utc` by `ZoneInfo("UTC")`
- Improve release workflow using `uv build` and `uv publish`
- Improve docker-publish workflow to use `uv build`

Feature
- Add support for Python 3.13 and deprecate Python 3.9

Refactor
- [Breaking] Add new metadata model: Requests now use `parameters` instead of `parameter` and `resolution` e.g. `parameters=[("daily", "kl")]` instead of `parameter="kl", resolution="daily"`

Fix
- DWD Road: Use correct 15 minute resolution

Refactor
- Bump polars to `>=1.0.0`
- Change `DWDMosmixValues` and `DWDDmoValues` to follow the core `_collect_station_parameter` method
- Allow only single issue retrieving with `DWDMosmixRequest` and `DWDDmoRequest`

Fix
- Fix `state` column in station list creation for DWD Observation