Add admin firmware upload support

Implement authenticated HTTPS OTA uploads with bounded streaming, image
validation, reboot coordination, and lifecycle exclusion. Add the admin
UI,
regression tests, and Phase 10 acceptance documentation.

src/web_cookie_auth.c

@@ -218,12 +218,18 @@ esp_err_t web_cookie_auth_require(httpd_req_t *r, bool mutation, bool upgrade,
     return require(r, mutation, upgrade, 0, view, allowed);
 }
 
-esp_err_t web_cookie_auth_require_json(httpd_req_t *r, size_t body_limit,
+esp_err_t web_cookie_auth_require_body(httpd_req_t *r, size_t body_limit,
                                       web_session_view_t *view, bool *allowed)
 {
     return require(r, true, false, body_limit, view, allowed);
 }
 
+esp_err_t web_cookie_auth_require_json(httpd_req_t *r, size_t body_limit,
+                                      web_session_view_t *view, bool *allowed)
+{
+    return web_cookie_auth_require_body(r, body_limit, view, allowed);
+}
+
 static bool secret(char out[65])
 {
     uint8_t bytes[32];