feat(annotations): draw on the world by hand (#547)

Supersedes #235 by @cora-fresh-labs, ported onto the current component layout with fixes from review.

Verified before merge: format, package boundaries, unit suite, build, and the browser tracking suite; a browser harness for the change where one applies; adversarial review applied.

Future work (not in this PR): hand-drawn marks do not persist across a reload today, and neither do spoken annotations; there is no storage layer for marks. The natural home is Scenes: a drawing that belongs to a shot and persists per shot, so a scene animation can carry its own marks. Needs an owner.
Co-authored-by: Clint Borle <[email protected]>

docs/CURRENT-STATE.md

@@ -3002,6 +3002,23 @@ are omitted rather than framing the wrong part of the globe.
 - Console/dev API: `window.__gevAnnotations.tour()`, `.demo()`, `.annotate()`, `.clear()`, `.count()`, and `.list()` are the deterministic no-mic test surface.
 - Current known resolver gap: mall/lifestyle districts such as "The Domain, Austin" can prefer a named building over the broader retail envelope. Product decision is that districts should become envelope + key buildings, but the scoring change still needs a careful multi-case validation pass.
 
+### Manual Whiteboard Drawing (September 2026)
+
+- DISPLAY ▸ **Draw** turns the globe into a whiteboard drawn by hand. Pick a shape (Area, Line, Pin), click the vertices on the real world, type an optional label and pick a colour, and finish. **Keyboard contract, live only while Draw is on and never while you are typing in another field:** Enter finishes the shape (as does a double-click, and the two cannot both submit it — the session is replaced before the annotate call is awaited); Backspace removes the last vertex; Esc cancels the shape in progress, and a second Esc — Esc on an empty session — leaves draw mode. Typing in the label field keeps Backspace; Enter there also finishes. **Clear** wipes the board (the shape in progress and every placed mark), so removing marks does not require the console or the microphone.
+- Runtime entry: `createApplicationTools` (`src/app/tools.js`, behind the `src/standalone/tools.js` shim) calls `initDrawTool({ viewer, annotations })` after `initAnnotations` and defers its `destroy()`, so disposing the shell returns every DOM listener, the Cesium handler, the preview data source, the borrowed click actions and the `window.__gevDrawTool` handle. Its markup is a DISPLAY-rail component template (`src/ui/templates/display-controls.html`), assembled into `index.html` at build time. That handle (`setActive`, `setShape`, `addVertex(lon, lat)`, `finish`, `cancel`, `clearAll`, `diagnostics`) is the no-mouse test seam.
+- Contract: a finished shape is submitted through the SAME `annotationEngine.annotate()` the voice agent uses, with geometry supplied and `manual: true` (`type: area` + `ring`, `type: route` + `path`, `type: pin` + coordinates). `resolveSpec` short-circuits manual specs (`resolveManualSpec`) so no geocoder, Places or Overpass call is made. A drawn area is a real (not synthesized) outline and drapes solid; a drawn line is a `route` with `mode: 'manual'`, labelled with its length and never a travel time; a pin is a point. Drawn marks therefore render with the whiteboard look, persist, de-dup, appear in `.list()`, and clear with `clear_annotations` / `.clear()`.
+- **A vertex is a lon/lat, and the mark is DRAPED.** Clicks are picked through `pickWorldFromScreen` — one of two scene helpers the annotation resolver factory (`src/annotations/resolver.js`) exposes alongside `sampleGroundHeight`, so the app has ONE depth-aware pick cascade rather than a second written beside it — which returns the height the pick landed on as well as the coordinate, so the live preview hangs on the roof or hillside under the pointer instead of sinking to sea level. The world renderer draws areas and routes with `clampToGround`, so the height is dropped at finish in one place (`finishSpec`) rather than being carried downstream and discarded silently: what you get is the outline you drew, lying on the surface beneath it.
+- **Draped marks classify onto `ClassificationType.BOTH`** — terrain AND 3D tiles — not onto 3D tiles alone. With only `CESIUM_3D_TILE`, every area fill, area outline, route and arrow rendered to nothing on a keyless boot, where Cesium's own globe carries Esri/OSM imagery and there are no tiles to classify against; the labels appeared and the geometry did not. That hit spoken annotations exactly as hard as hand-drawn ones. `scripts/qa-draw-tool.mjs` counts the mark's own colour in the rendered frame before and after a shape is finished, on a keyed AND a keyless server, so "the board says there is a mark" can no longer pass for "the mark is on screen".
+- **A finished area is a CLOSED ring.** The fill polygon closes itself but the outline beside it is a polyline, so an open ring drew every edge except the one back to the first vertex — a triangle with two sides. `finishSpec` repeats the first position at the end. A line is never closed: joining its ends would invent a segment nobody drew.
+- **Measurements and centres are computed on unwrapped longitudes** (`unwrapLongitudes` / `wrapLongitude` in `drawMode.js`, used by `ringAreaM2`, `ringCentroid` and the engine's manual-area anchor). A ~50,000 m² rectangle straddling the antimeridian reads its 0.002° width as 359.998° under raw arithmetic: it measured thousands of square kilometres and anchored on the Greenwich meridian, half a world from the shape. Path length was already safe — haversine is periodic in the longitude delta — and a test pins that so a "fix" cannot break it.
+- **Bounds.** One shape holds at most `MAX_VERTICES` = 512 points; two clicks within 0.5 m are one vertex (that is what makes a double-click finish without leaving a stray point); a vertex that is not a finite on-globe coordinate is refused. A shape that encloses nothing is refused rather than placed: three collinear points are not an area and a line under a metre long is not a line, and the hint says which.
+- Pointer ownership: while a session is open the tool holds the single pointer claim (`claimPointer('draw')`, `src/data/inputOwnership.js`) and **every** ambient scene selection handler — the shared tracking click gesture behind flights, military and CCTV, plus vessels, satellites, launches, fires, installations, bikeshare, radio, submarine cables, the bundled GeoJSON layers and the CCTV calibration gizmo — returns before picking. A vertex over an aircraft is a vertex, not a selection.
+- **The claim is a LEASE.** `claimPointer(owner)` returns an opaque token or `null`; `releasePointer(lease)` takes that token. A second claim fails even under the same owner name, because two live instances of one tool — an old one mid-teardown and its replacement — are two owners; releasing by name let the old instance free the claim its successor was holding, and every layer started selecting through the live session's vertices. A superseded lease now releases nothing.
+- **Cesium's own click actions are borrowed too.** The Viewer binds a selecting LEFT_CLICK and a tracking LEFT_DOUBLE_CLICK on its own handler, outside every layer and therefore outside the shared claim — guarding the layers alone still left a drawn vertex selecting the entity under it. Both are removed for the session and restored, as the same function objects, when it ends or the tool is destroyed.
+- **Enter belongs to whatever has the keyboard.** The finish key is taken only from the canvas, the page body and the tool's own label field. With a control focused — Clear, a shape button — Enter activates that control, as a keyboard user expects; it does not quietly finish the shape.
+- Pure half: `src/annotations/drawMode.js` (session, minimum vertices, double-click de-dup at 0.5 m, vertex ceiling, degenerate-geometry refusal, ring closing, dateline-safe length/area/centroid, hint text). Regression surface: `src/annotations/drawMode.test.mjs` and `src/data/inputOwnership.test.mjs` (pure), `src/annotations/drawToolBehaviour.test.mjs` (the tool driven against DOM and viewer doubles — leases, borrowed input actions, teardown, the Enter key, preview heights), `src/annotations/drawTool.test.mjs` (structural: where files live, which ids the markup carries, what the docs may claim), and the rendered harness `scripts/qa-draw-tool.mjs`.
+- The annotation tree is a declared ownership group: `./annotations` → `src/annotations/index.js` in `package.json`, with its module graph listed in `scripts/package-boundaries.json`, so an annotation module reaching outside that graph is a gate failure rather than a surprise in a layer's bundle. `drawMode.js`, `drawTool.js` and their tests are in `scripts/format-scope.json`.
+
 ### 3D Aircraft + Tracking (June 2026)
 
 - **The TRACKED contact's 2D↔3D handoff is DEFAULT behaviour (2026-08-19), driven by camera distance alone.** It does NOT consult the DISPLAY-rail `3D` toggle, which continues to own the FLEET (the un-instanced draw-call budget stays the operator's decision). Policy lives in `src/data/trackedModelRegime.js` and is shared by both layers: enter below `TRACKED_MODEL_ENTER_ALT_M` = 150,000 m and hand back to the billboard only above `TRACKED_MODEL_EXIT_ALT_M` = 172,500 m. **The swap distance was set by playtesting on 2026-08-20:** a first pass at 1,000,000 m switched too early; 2D reads correctly at ~600 km and the handoff belongs at ~150 km. **Consequence, recorded on purpose:** the tracked contact now enters 3D NEARER than the FLEET does (`MODEL_ALT_CEIL_M` = 800,000 m, unchanged), so with the DISPLAY-rail `3D` toggle on, 150–800 km draws surrounding contacts as models while the selected one is still a glyph. Nothing double-draws (the fleet pass skips the tracked icao) and aligning the two is a fleet-side decision, deliberately out of scope. **The two thresholds are asymmetric on purpose:** a single threshold makes a tracked orbit sitting ON the boundary strobe billboard↔model as the camera's altitude wobbles across it. Do not collapse them. The latch is scoped per selection, so a new target re-evaluates against the ENTER ceiling rather than inheriting the previous target's exit band. Exactly ONE model is involved; it loads on demand when the regime opens, is HIDDEN (not released) on regime exit so re-entry has no load gap, and is released by the existing teardown on deselect/re-track/destroy. Cockpit and TR-3B suppression are unchanged. **Two invariants around it:** (a) the hysteresis latch AND the load-failure latch are per-selection state cleared by `_resetTrackedSelectionState()` in the tracking lifecycle (deselect / re-track / cross-layer / init / destroy) — the predicate's icao-change guard is defence only, since it needs a drawn frame while nothing is selected and the render governor's idle mode does not promise one; (b) on-demand loading is bounded at 3 attempts per selection with a 1.5 s backoff and one console warning naming the asset — the driver runs every `scene.preUpdate`, so an unbounded catch means a missing GLB spins load→reject at frame rate. The billboard stays the visual throughout a failed load.