Impact mode formula changed from (ds+1)×pw/ew to (ds+1)×pw/ew^0.25
so that effort no longer perfectly cancels priority for standalone
tasks. High-priority high-effort work now ranks above medium-priority
low-effort work, matching impact mode's intent of favoring importance
over cost.

Embedding raw ANSI escape codes in cell strings causes comfy-table to
count them as visible characters when calculating column widths, shifting
headers out of alignment with their data columns.

Replace format!() with raw escapes with Cell::fg() and
Cell::add_attribute() across list, ready, next, and search. Add
cell_bold() and cell_fg() helpers in color.rs that conditionally apply
styling based on the existing NO_COLOR / TTY checks.

Cover both scoring modes, verbose output, limit, empty case, and JSON
output. Update SKILL.md and README.md.

Add next to cli.rs, cmd/next.rs, and cmd/mod.rs. Queries open tasks and
blocker edges from the DB, feeds them to score::rank(), and renders
results using comfy-table with a header row.

Add src/score.rs with the core algorithm for the next command: build the
blocker DAG from open tasks, compute transitive downstream scores, and
rank ready tasks using mode-dependent formulas.

show displays all blocker edges regardless of status, making tasks appear
blocked when their blockers are closed. Split the display into open
blockers (actually blocking) and resolved ones.

list and ready display priority and effort as bare low/medium/high in
adjacent columns with nothing distinguishing them. Add a header row to
each using comfy-table's set_header().

Replace hardcoded format!() spacing with comfy-table across all commands.
Fix missing effort column in list output.

Prevent circular dependencies in the blocker graph by walking the existing
edges from the proposed blocker back toward the task. Reject with a clear
error if a cycle would be created.

jj hard