Podcast USB v0.5.0

WHAT CHANGED IN v0.5

- USB/feed matching accepts cleaned, rearranged and partial episode names.
  Original IDs take priority. Episode/campaign and main/Second Wind identity
  are checked; file length can disambiguate otherwise identical main/bonus
  titles. Ambiguous matches require a starting-point choice instead of silently
  falling back to the oldest episodes when existing files/history are present.
- The campaign-code checkbox is removed. Phrase removal is the visible control.
  Existing Stinky Dragon campaign cleanup migrates to C01 -, C02 -, C03 - lines
  without duplicating any existing entries. Prefix/suffix settings are retained.
- Remove podcast confirmation names the subscription. Cancelling sends no
  removal request; PC and USB files are not deleted by subscription removal.
- Review starts title previews immediately, displays an explicit loading state,
  retries one transient failure and provides a Retry button if needed. Cleanup
  is also previewed for unselected episodes; only numbering waits for selection.
  The final track prefix is highlighted as one complete addition.
- Activity is one fixed list in Review's podcast/track order, grouped by show.
  All new and kept-file rows exist before processing starts. Updating an action
  never moves a row. Click the filename for that episode's history/skip control.
- Separate estimates cover the entire audio queue, the whole preparation stage,
  and the current audio task. Measurements account for remaining conversions,
  MP3 copying/tagging and downloads that must finish before processing. Speeds
  are learned from the current run and saved for future runs. Unknown sizes or
  rates show Estimating rather than a false finish time.
- The USB summary replaces the preparation summary when transferring starts.
  Whole USB update remaining and Current file remaining are labelled separately.
  Total USB estimates/progress include copying, verification and final file/folder
  placement/index cleanup. The close prompt also shows whole-stage estimates.

