feat: v0.2–v0.5 — decorations, completions, hover, commands, status bar

[jimblom]

What's in this PR

Implements roadmap milestones v0.2 through v0.5, plus a structured completion provider architecture that supersedes PR #3.

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v0.2 — Visual completeness

Done-task strikethrough
[x] task lines now render with strikethrough and a muted foreground color. Configurable via hexfield.colors.doneTask (default #6B737C). The decoration covers the full task line so completed work visually recedes without relying on color alone.

Frontmatter block highlight
The YAML frontmatter block receives a subtle background tint across all its lines, making the metadata section visually distinct from task content.

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v0.3 — Editor intelligence

Hover tooltips (HoverProvider scoped to hexfield-markdown)

• Due dates — human-readable proximity: "3 days overdue (Tuesday, Feb 10)", "Due today", "Due in 5 days — Friday, March 12"
• Time estimates — expanded form: est:90m → "1h 30m", est:1.5h → "1h 30m"
• Project tags — shows color and a clickable URL link if defined in hexfield-deck.projects

Project tag autocomplete (via HexfieldCompletionService — see below)
Typing # in a Hexfield planner file offers completions from two sources: project names in hexfield-deck.projects config, and tags already used in the current document. Partial input is replaced, not appended.

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v0.4 — Commands & snippets

Hexfield: Insert Date
Opens a quick-pick menu with preset options (today, tomorrow, end of week, next Monday, 1 week, 2 weeks, 1 month) and inserts [YYYY-MM-DD] at the cursor. Only visible in the command palette when a Hexfield file is active.

Hexfield: Jump to Today
Scrolls to the day-section heading that matches today's day name. Falls back to a message if no matching heading is found.

Snippet pack (active in hexfield-markdown files)

Prefix	Expands to
hfm	Full frontmatter block for a new planner file
hfd	Day section heading with a starter task
hft	Full task line with all token slots
est	est: with an inline preset choice list
phi / pme / plo	Priority HIGH / MED / LOW markers

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v0.5 — Status bar

When a Hexfield planner file is active, a summary appears in the right status bar:

⚠ 2 overdue  ↻ 3 active  ○ 8 open

Updates within 500ms of edits. Hides automatically when a non-Hexfield file is focused.

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Completion provider architecture (supersedes PR #3)

Introduces a HexfieldCompletionService layer between VS Code's CompletionItemProvider interface and individual per-token providers:

• src/completions/completionService.ts — defines HexfieldSubProvider interface and the service, which registers once and fans out to all active providers. Trigger characters are derived automatically.
• src/completions/providers/projectTagProvider.ts — the only active provider; incorporates PR Claude/language specific suggestions rh pxb #3's replace-range logic.

Adding a new token type (estimates, checkboxes, dates) means implementing HexfieldSubProvider and adding one line in extension.ts. No other changes needed.

PR #3 is superseded by this PR — all of its logic is preserved in ProjectTagProvider.

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Test plan

Setup

• Open VS Code with this branch installed (F5 from the repo, or install the .vsix)
• Open examples/weekly-planner.md — confirm it activates as hexfield-markdown (check the language indicator in the status bar bottom-right)

v0.2 — Visual completeness

• Done-task strikethrough — any [x] line should render with strikethrough text and a muted gray color
• Frontmatter highlight — the --- block at the top of the file should have a subtle background tint distinguishing it from the task content
• Demotion clears decorations — remove type: hexfield-planner from frontmatter, save; all colorization including the frontmatter tint should disappear immediately

v0.3 — Hover tooltips

• Overdue date — hover over a [YYYY-MM-DD] that is in the past; tooltip should say "Overdue — N days ago (Day, Month Date, Year)"
• Future date — hover over a future date; should say "Due in N days — ..."
• Today's date — hover over today's date; should say "Due today"
• Time estimate — hover over est:4h; tooltip should say "4 hours"
• Estimate in minutes — hover over est:90m; tooltip should say "1h 30m"
• Project tag (no config) — hover over #deep13; tooltip should show #deep13 with no extra fields
• Project tag (with config) — add a project with a color to hexfield-deck.projects settings; hover the tag; tooltip should show the color

v0.3 — Tag autocomplete

• On a task line, type # — a completion list should appear with project names
• Type #hex (partial) — the list should filter; selecting a completion should replace #hex, not append
• No spurious completions — type # in a regular .md file (no type: hexfield-planner frontmatter); no Hexfield completions should appear
• No completions for other tokens — type est: or [ in a Hexfield file; no completion list should appear (this is intentionally disabled for now)

v0.4 — Commands

• Open command palette (Ctrl+Shift+P) in a Hexfield file; Hexfield: Insert Date should appear
• Run Hexfield: Insert Date; pick an option; [YYYY-MM-DD] should be inserted at the cursor
• Run Hexfield: Jump to Today; the editor should scroll to today's day heading in the weekly planner
• Command palette scoping — open a regular .md file; Hexfield: commands should not appear in the palette

v0.4 — Snippets

• In a Hexfield file, type hfm and trigger snippet (Tab or select from IntelliSense); frontmatter block should expand with tab stops
• Type hfd; day section heading should expand
• Type hft; full task line should expand with all token placeholders
• Type est and select the snippet; should expand with an inline choice list for the value

v0.5 — Status bar

• With weekly-planner.md open, a task summary should appear in the bottom-right status bar
• Overdue count, active count, and open count should reflect the file contents
• Edit a [ ] to [x]; within 500ms the open count should decrease
• Switch to a non-Hexfield file; the status bar item should disappear
• Switch back; it should reappear