feat: confirm pharmacy deletion and migrate models

[Roman-Andr]

Impact

• adds a per-pharmacy delete button on the right side of every row
• requires a second click within five seconds: the cross changes to a check mark, then resets if deletion is not confirmed
• removes the selected pharmacy instead of only the final row
• migrates all production and test data models from dataclasses to Pydantic models
• preserves immutable model behavior with frozen models and rejects unknown fields

Root cause

Pharmacy rows had no targeted delete action or confirmation state; the only existing action removed the last row immediately. Structured models were also split between Pydantic and dataclasses, which left validation and copy semantics inconsistent across the application.

Validation

• uv lock --check
• uv run ruff check .
• uv run mypy
• env -u DISPLAY -u WAYLAND_DISPLAY uv run pytest - 330 passed, 16 GUI tests skipped locally because Xvfb is unavailable
• uv run pyinstaller --noconfirm pharmparser.spec
• ./dist/pharmparser-cli --help

Screenshots

A local screenshot is not attached because this release environment has no working display server or Xvfb. The delete-button behavior has unit and GUI regression coverage; the GitHub Linux job runs the GUI suite under Xvfb.

[Roman-Andr]

Superseded by #20: GitHub marked the shared dev history as non-rebaseable. #20 contains the byte-for-byte identical checked tree on a clean main base, so the required rebase merge can proceed without rewriting dev.