chore(sec-touch): fix review comments

Author: distante

.specs/sniffer.md

@@ -99,4 +99,4 @@ Note: discovered state is held in RAM only. After a device restart or firmware f
 2. Turning scan mode on stops normal polling and listener updates; the text sensor populates with discovered IDs across the configured range.
 3. Turning scan mode off mid-scan resumes normal polling immediately; the saved position is used when scan mode is turned on again.
 4. When scan mode runs to completion, polling resumes automatically and the binary sensor reflects the off state.
-5. IDs with registered listeners do not appear in passive capture output, but do appear in scan mode output.
+5. IDs with registered listeners do not appear in passive capture output and are skipped in scan mode, so they do not appear in scan output either.  

components/sec_touch_sniffer/sec_touch_sniffer.cpp

@@ -60,6 +60,8 @@ void SecTouchSniffer::toggle_scan() {
 
   if (this->scan_end_ == 0) {
     ESP_LOGW(TAG, "toggle_scan() called but no scan range configured — ignoring");
+    this->is_scanning_ = false;
+    this->update_scan_switch_();
     return;
   }
 

components/sec_touch_sniffer/sec_touch_sniffer.h

@@ -19,7 +19,7 @@ struct SniffedEntry {
 class SecTouchSniffer : public Component, public text_sensor::TextSensor {
   static constexpr const char *TAG = "SecTouchSniffer";
   // Text sensor payload cap: keeps output within comfortable MQTT/API packet sizes.
-  // Each entry is ~35 chars; 255 chars fits ~7 entries before truncation.
+  // Each entry is ~35 chars; 2048 chars fits ~58 entries before truncation.
   static constexpr size_t MAX_STATE_LEN = 2048;
 
  public: