Tape measure, area templates, map markers with notes

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HJhXuLD2Z6hv3Wqeq9UL9K

README.md

@@ -170,6 +170,8 @@ Players only see a short card of the other players, never their sheets. Guessing
 
 - **Map ping**: everybody (players and DM) can point at a spot: double-click the map, or press *📍 Ping* and click. All see a ring in the pinger's colour with their name, and hear a short ping (rate limited to one per second and person). The DM can switch the sound off or upload an MP3 for it under *Lobby actions → Sounds → Map ping*; players can still mute sounds for themselves.
 
+- **Measure, areas, markers** (for everybody, buttons above the map): *📏 Measure* - click start and end, the distance in squares is shown to the whole table for a few seconds. *⬡ Area* - spell templates (circle, cone with adjustable angle, line with width, square) in the colour of whoever placed them, visible to all until their author or the DM removes them (list top left, DM can clear all); they disappear when the map changes. *📌 Marker* - pins with icon, title and note on the map. Markers are private to their author until "Show to everybody at the table" is ticked; the DM can remove shared markers. They belong to the map, so they are back when you return to that map.
+
 ## API
 
 All `/api/*` routes except `/api/auth/me`, `/api/auth/register` and `/api/auth/login` need the session cookie.
@@ -201,6 +203,9 @@ All `/api/*` routes except `/api/auth/me`, `/api/auth/register` and `/api/auth/l
 | PUT | `/api/lobbies/{id}/doors/{wall}` , `/sight` | DM: open / close a door; line of sight on / off |
 | GET / POST | `/api/lobbies/{id}/scenes` | DM: saved scenes / save a copy of the table (`name`) |
 | PUT / DELETE | `/api/lobbies/{id}/scenes/{sid}` | DM: rename (`name`), save now (`save`) / delete |
+| POST | `/api/lobbies/{id}/measure` | Share a measured distance (`x1,y1,x2,y2`) |
+| POST / DELETE | `/api/lobbies/{id}/templates[/{tid}]` | Place an area (`kind, x, y, dir, size, width`) / remove (author or DM; DELETE without id: DM clears all) |
+| POST / PUT / DELETE | `/api/lobbies/{id}/marks[/{kid}]` | Marker with note (`x, y, icon, title, note, shared`) / edit (author) / remove |
 | POST | `/api/lobbies/{id}/ping` | Ping a spot (`x`, `y`); everybody gets a push |
 | PUT | `/api/lobbies/{id}/scene` | DM: switch to a scene (`scene_id`); the current one is saved first |
 | GET / POST / DELETE | `/api/props[/{id}]` | Your own prop images / upload (raw body, `?name=`) / delete |