Code quality cleanup: knip config, type consolidation, ADR, and TODO fixes

[IanMayo]

Summary

Five targeted code-quality improvements bundled into a single PR to reduce reviewer overhead while clearing accumulated technical debt and false positives.

Changes

• Knip false-positive silencing: Added root knip.json with specs/** ignore pattern to silence 57 false-positive "unused" reports from speckit contracts. Pinned knip to 5.88.1 in root devDependencies to eliminate tool-version drift between contributors.

• LogPanel prop consolidation: Merged LogTimelineProps and LogByFeatureProps into a single LogPanelProps interface in shared/components/src/LogPanel/types.ts to eliminate interface drift and reduce future review ambiguity.

• ADR-019 documentation: Documented two accepted import type-only cycles in the VS Code extension (mapPanel → activityPanelView → calcService and activityPanelView → resultsPanelService) in docs/project_notes/decisions.md. Both cycles are erased at runtime; interface extraction is the eventual fix but deferred as a larger refactor.

• Loader plotName fix: Replaced // TODO: Get actual name from plot list placeholder in apps/loader/src/renderer/hooks/useLoadWorkflow.ts with proper lookup that threads the plot's display name from the plot list. Added regression test in apps/loader/tests/unit/useLoadWorkflow.test.ts with revert-and-red validation.

• TODO promotion: Replaced bare // TODO: markers in the loader with TODO(#472): and TODO(#473): references, linking to newly filed GitHub issues #472 and #473. Added pre-push grep guard to prevent shipping literal placeholders.

• Cleanup: Removed orphaned shared/components/diff/ staging artifact with zero consumers.

Implementation Notes

• Test-first approach for the plotName fix: revert-and-red sanity check confirmed the test is a real gate, not a tautology.
• Pre-push grep guard (grep -rn "TODO(#NNN)" apps/) enforces TODO promotion discipline at commit time.
• Knip pinning to root devDependencies ensures pnpm install on a clean clone resolves to the same binary across all contributors.

https://claude.ai/code/session_018BQTrz526CuYqTGQZm5hC8