Instead of walk-everything-first then index, workers now receive files
the instant os.walk yields them. The thread pool is open before the
walk starts; each discovered file is submitted immediately. Completed
futures are drained after each directory to keep memory flat.
Progress message shows:
"Discovering & indexing (8w): 1,234 — 5,678 found so far"
then once walk finishes:
"Indexing (8w): 8,000 / 9,100"
UI: merged Discovery + Indexing into a single "Discover + Index" phase pill.
Indeterminate progress bar stays on until total file count is known.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Scanner now updates message every 250 files during os.walk so the UI
shows a live count. Progress bar switches to an indeterminate animated
pulse during discovery and takeout phases (no known total yet), then
reverts to a normal percentage bar once indexing begins.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
New GET /api/browse endpoint lists subdirectories at any path.
UI gets a folder icon button next to each path input that opens
a browsable directory tree modal. Escape or Cancel closes it,
clicking a folder navigates into it, Select confirms the choice.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>