# OPDS Per-Server Default Save Directory

## Task
Add a configurable default download path per OPDS server. The directory picker now starts at the server's saved path instead of always at root. New servers default to "/".

## Changes Made

### Modified files
- **`src/OpdsServerStore.h`** -- Added `downloadPath` field (default `"/"`) to `OpdsServer` struct.
- **`src/OpdsServerStore.cpp`** -- Serialize/deserialize `download_path` in JSON. Existing servers without the field default to `"/"`.
- **`src/activities/settings/OpdsSettingsActivity.cpp`** -- Added "Download Path" as field index 4 (shifted Delete to 5). Uses `DirectoryPickerActivity` as subactivity for folder selection. Displays current path in row value.
- **`src/activities/util/DirectoryPickerActivity.h`** / **`.cpp`** -- Added `initialPath` constructor parameter (default `"/"`). `onEnter()` validates the path exists on disk and falls back to `"/"` if not.
- **`src/activities/browser/OpdsBookBrowserActivity.cpp`** -- Passes `server.downloadPath` as `initialPath` when launching the directory picker.
- **`lib/I18n/translations/*.yaml`** (all 9 languages) -- Added `STR_DOWNLOAD_PATH` with translations.
- **`lib/I18n/I18nKeys.h`**, **`I18nStrings.h`**, **`I18nStrings.cpp`** -- Regenerated.

## Follow-up Items
- Test on device: verify settings UI shows/saves path, picker opens at saved path, fallback works when directory is removed