Add public endpoint to get user photo

app/controllers/api/v1/Auth.controller.js

@@ -220,6 +220,28 @@ class AuthController extends Controller {
         return res.api(await user.to_api())
     }
 
+    async get_user_photo(req, res, next) {
+        let user
+        if ( req.params.id === 'me' ) {
+            user = req.user
+        } else {
+            const User = this.models.get('auth:User')
+            user = await User.findOne({ uid: req.params.id })
+        }
+
+        if ( !user )
+            return res.status(404)
+                .message(req.T('api.user_not_found'))
+                .api()
+
+        const file = await user.photo()
+        if ( !file )
+            // The user does not have a profile. Send the default.
+            return res.sendFile(this.utility.path('app/assets/people.png'))
+
+        await file.send(res)
+    }
+
     async create_group(req, res, next) {
         if ( !req.user.can(`auth:group:create`) )
             return res.status(401)