Blocks are now selected without auto-starting the timer. Clicking a block
makes it current (highlighted) but leaves it in a ready state. A "Start"
button (indigo) triggers timing for a fresh block; "Resume" appears for
previously-worked blocks; "Pause" remains while running.
Also fixes the sidebar duration label to show "Done!" when elapsed ≥ total
and "< 1 min" for sub-minute remaining time instead of "0 min".
Backend adds a "select" event type that records an implicit pause for the
previous block, updates current_block_id, and broadcasts is_paused=true
with prev_block_elapsed_seconds so the TV sidebar stays accurate.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
derekc
cc599603cf