BACK-401/489/490 - Task dates, project health, overview statistics (split 7/9 of #669)

[MrLesk]

Note

Maintainer-split slice 7/9 of #669. All commits are authored by @kuwork — I only rebased them onto current main and resolved conflicts. Merge with Rebase and merge to keep the per-task commits and original authorship.

Stack

Based on pr669/6-net-wiki-fixes (slice 6). Review only the commits unique to this PR. After the previous slice merges, restack with git rebase --onto main pr669/6-net-wiki-fixes pr669/7-dates-stats.

Tasks in this slice

BACK-401 — dueDate, plannedStart, plannedEnd for tasks and milestones (CLI, TUI, Web, MCP)

• New optional date fields on Task and Milestone with round-trip markdown serialization
• CLI flags, MCP schema updates, web date pickers

BACK-489 — Project health indicators: at-risk / overdue / stale

• src/core/statistics.ts: calculateHealth() with dueDate awareness
• Statistics.tsx health dashboard; health dot on task cards

BACK-490 — CLI overview statistics

• src/commands/overview.ts: --watch, --format, --output options
• ⚠️ Review flag: main already has backlog overview with a blessed-based interactive TUI (src/ui/overview-tui.ts), which BACK-469 recently made theme-adaptive. This commit replaces that implementation with a picocolors plain-text renderer, discarding the BACK-469 improvements to this file. This needs an explicit decision — it is a rewrite of an existing feature, not an addition.

Fix Task Time Problem (unlabeled commit)

• Only corrects frontmatter dates in six fork task files; harmless metadata fix.

Notes

• Split adjustment: BACK-401's rewrite of handleUpdateMilestone silently dropped main's newer rename flow (milestone reload + milestone in the response, which server-search-endpoint.test.ts asserts). Restored main's response contract while keeping the new date fields.
• Split adjustment: the mcp-server.test.ts tool-list expectation was updated to milestone_edit inside BACK-401 (the commit that renames the tool) instead of arriving in slice 8, so this slice's tests pass standalone. The milestone_rename → milestone_edit rename itself is a breaking MCP-surface change that still needs an explicit decision.
• Task IDs in backlog/tasks/ were minted on the fork — re-mint before merge if taken.
• Validated at this tip: bun install --frozen-lockfile, bunx tsc --noEmit.

Original combined PR: #669.

Full stack: #675 editor/paste → #676 wiki → #677 i18n → #678 doc editing → #679 search/sidebar → #680 fixes → #681 dates/stats → #682 Gantt → #683 timezone/polish — split from #669, all commits authored by @kuwork.