M7: touch + outbound /state POST to Scrypted

state_client.{h,c}:
- Worker task drains a depth-1 queue (xQueueOverwrite gives the
  replace-on-full semantics from the spec — in-flight POST is never
  cancelled; the next queued entry is overwritten by newer state).
- esp_http_client POST to <scrypted>/state with Content-Type application/
  json, User-Agent ScryptedViewport/<version>, Connection: close, 1s
  timeout. Body: {"viewport":"<name>","state":"wake"|"sleep"}.
- Any non-2xx or transport error increments state_post_failures and is
  otherwise ignored. Silently drops if no Scrypted URL is configured.

touch.{h,c}:
- FT5426 capacitive touch on the shared I2C bus at 0x38.
- 30ms polling task; tracks down/up transitions, detects taps as
  down-then-up within 500ms with a 150ms debounce.
- On tap, toggles wake/sleep via state_machine_set_local(), which drives
  the local transition AND fires state_client_post() at Scrypted.

state_machine adds state_machine_set_local(): runs the same transition
as state_machine_set() then enqueues an outbound POST. Idle-timer
expiry now uses this path so Scrypted sees idle-driven sleeps too
(the spec's "tighten the race with /frame 409" path stays in place as
the fallback).

display.h exposes display_i2c_bus(); touch.c uses it instead of
re-initializing the same I2C port.

app_main starts state_client right after the state machine and starts
touch after display init (touch is skipped if display isn't up since
they share the bus).

CMakeLists.txt: add esp_http_client to REQUIRES.

Build clean against ESP-IDF 5.4 (binary ~860 KB; jumped ~210 KB from
M6 because esp_http_client + cJSON path pulls in tcp_transport, mbedtls,
http_parser).

TESTING.md M7: flask-based test receiver, tap dispatch verification,
failure-path check (kill receiver, confirm counter increments),
queue-coalescing behavior, no-POST-on-Scrypted-initiated, no-POST-
when-unconfigured.

1 files changed, 10 insertions, 1 deletions

diff --git a/main/app_main.c b/main/app_main.c
index 126bf15..e7bff0a 100644
--- a/main/app_main.c
+++ b/main/app_main.c
@@ -4,7 +4,9 @@
 #include "mdns_service.h"
 #include "net_eth.h"
 #include "nvs_config.h"
+#include "state_client.h"
 #include "state_machine.h"
+#include "touch.h"
 #include "viewport_state.h"
 
 #include "esp_event.h"
@@ -32,6 +34,7 @@ void app_main(void)
     }
 
     ESP_ERROR_CHECK(state_machine_init());
+    ESP_ERROR_CHECK(state_client_init());
     ESP_ERROR_CHECK(mdns_service_start());
     ESP_ERROR_CHECK(http_api_start());
 
@@ -62,6 +65,12 @@ void app_main(void)
         ESP_LOGW(TAG, "jpeg decoder init failed — /frame will be unavailable");
     }
 
-    // TODO M7: Capacitive touch -> outbound /state POST to <scrypted>/state
+    // Touch shares the panel I2C bus; only meaningful if display came up.
+    if (display_is_up()) {
+        if (touch_init() != ESP_OK) {
+            ESP_LOGW(TAG, "touch init failed — taps won't work");
+        }
+    }
+
     // TODO M8: Local screens (IP, loading) + BOOT button
 }