v2.7.1

Pure-refactor and release-tooling release. No behaviour, API, dependency,
binary-size, or feature changes.

Internal

• Split src/handler/action/tests.rs (2928 LOC, one file) into a
  tests/ directory with one file per pre-existing logical section
  (basic, state_transition, sequence, edge_cases, focus,
  scroll_bounds) plus a mod.rs that owns the shared helpers and the
  call_handle_action! macro.
• Split src/render/status.rs (1644 LOC, one file) into a status/
  directory: bar.rs (density variants + budget segment), format.rs
  (file metadata + size/time formatters), popup.rs (input/confirm/mini
  popups), help.rs (help overlay), todos.rs (TODO/FIXME popup), with
  mod.rs re-exporting the existing public renderers.

Fixed

• release.yml: the awk pattern range used to extract the per-version
  changelog section was collapsing to one line because the start header
  also matched the end pattern. Replaced with a state-machine scan so
  future tag pushes get the right notes auto-attached to the GitHub
  Release.

What's Changed

• Fix awk in release.yml so changelog section is extracted correctly by @Hiro-Chiba in #208
• Split handler/action/tests.rs into per-category modules by @Hiro-Chiba in #209
• Split render/status.rs into per-concern modules by @Hiro-Chiba in #210
• Release 2.7.1: internal refactor + release.yml fix by @Hiro-Chiba in #211

Full Changelog: v2.7.0...v2.7.1