Implement HTTPS lifecycle and reboot controls

src/web_server.h

@@ -39,7 +39,31 @@ typedef struct {
 /* Initialize runtime state without requiring valid certificate material. */
 esp_err_t web_server_init(void);
 
-/* Start one TLS-only server on all active network interfaces. */
+typedef struct {
+    uint32_t generation;
+    bool running;
+    bool transitioning;
+    bool controllable;
+} web_server_management_snapshot_t;
+
+/* Zero-wait, secret-free projection; controllable excludes failed cleanup and
+ * exhausted generations. No HTTPD work or owner wait is performed. */
+esp_err_t web_server_get_management_snapshot(web_server_management_snapshot_t *snapshot);
+
+/* Conditional lifecycle admission under the canonical server mutex. Call only
+ * off HTTPD, after caller-owned authorization and bounded ACK handoff. These
+ * APIs do not authenticate, acknowledge, cancel on revocation, or bound HTTPD
+ * shutdown time. Restart reserves the lifecycle through stop and start; a failed
+ * stop never starts another server. Stale/exhausted/unclean state rejects without
+ * side effects. Canonical stop/start below remain the recovery path. */
+esp_err_t web_server_stop_current(uint32_t expected_generation);
+esp_err_t web_server_restart_current(uint32_t expected_generation);
+/* Reserves this HTTPS generation before canonical whole-device esp_restart().
+ * Admission cannot be cancelled; normally does not return. Same caller rules. */
+esp_err_t web_server_reboot_current(uint32_t expected_generation);
+
+/* Start one TLS-only server on all active network interfaces.
+ * Start/stop may wait for HTTPD; never call from its task or queued callbacks. */
 esp_err_t web_server_start(void);
 esp_err_t web_server_stop(void);