Add versioned HTTP API routes

docs/dashboard-esp32s3.md

@@ -47,15 +47,15 @@ All grounds remain common.
 ## API endpoints consumed
 
 Minimum dashboard MVP:
-- GET /status
-- POST /relay/set
+- GET /api/v1/status
+- POST /api/v1/relay/set
 
 Potential later use:
-- GET /config
-- POST /config/save
-- POST /temps/scan
-- POST /temps/assign
-- POST /temps/clear
+- GET /api/v1/config
+- POST /api/v1/config/save
+- POST /api/v1/temps/scan
+- POST /api/v1/temps/assign
+- POST /api/v1/temps/clear
 
 ## MVP Display Goals
 
@@ -120,10 +120,10 @@ Then interactive:
 
 1. Dashboard boots.
 2. Connects to cargo ESP32 AP.
-3. Polls GET /status.
+3. Polls GET /api/v1/status.
 4. Shows disconnected state until valid JSON is received.
 5. Updates dashboard on a fixed interval.
-6. Relay buttons call POST /relay/set.
+6. Relay buttons call POST /api/v1/relay/set.
 
 ## Polling Guidance