fix(pr-management-stats): remove unused local variable in test_ready_split.py

[HeaTTap]

Fixes #957

Removed the unused local variable ctx in test_render_ready_split_empty_state inside tools/pr-management-stats/tests/test_ready_split.py as render_ready_split takes the dict payload directly without needing context.

[justinmclean]

Thanks for the fix.

Looking deeper I found another issue that you might also want to fix.

This defect existed because nothing in the repo could have caught it.

tools/dev/run-workspace-check.sh selects members for ruff by auto-discovery: ruff → runs only on members with [tool.ruff]. tools/pr-management-stats/pyproject.toml has no [tool.ruff] section, so workspace-ruff-check and workspace-ruff-format skip the member entirely. An unused local is ruff's F841, which is in the default rule set, so a linted member would have failed on this line the day it landed.

Three of the thirty workspace members are in that position:
tools/agent-isolation
tools/jira
tools/pr-management-stats

All three pin ruff in their dev dependency group, so the intent to lint them is clearly there. None uses the documented [tool.magpie.checks] skip opt-out, which is what a deliberate exemption would look like. This is silent drift of exactly the kind the workspace-membership guard was built to prevent, one layer down: the member is in [tool.uv.workspace] members, so check-workspace-members is satisfied, but the per-check auto-discovery still drops it.

Suggested follow-up: add [tool.ruff] to the three members and fix whatever that surfaces.