Update README to document Capture & Replay features

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README.md

@@ -170,6 +170,37 @@ Three dot indicators in the header show the current page.
     - Jamming started or stopped
     - TX power level changed
     - Radio reinitialization triggered by watchdog
+    - Signal detected during capture
+    - Capture/Replay started or stopped
+
+---
+
+## CAPTURE AND REPLAY
+
+The system includes a fully autonomous signal capture mode for recording and
+replaying raw fob signals directly into the ESP32 RAM.
+
+    [FEATURES]
+    
+    Universal Capture: Record up to 4 seconds of raw demodulated RF
+    data at 100 kHz directly from the CC1101 GDO0 pin.
+
+    Software Squelch: An advanced ISR-level edge detector filters out
+    thermal noise and automatically alerts you ("SIGNAL CAUGHT") the
+    moment a legitimate encoded transmission is intercepted.
+
+    Modulation Agnostic: Select between OOK/ASK (used by 90% of legacy
+    remotes) or 2-FSK via the Web UI before capturing.
+
+    Bitrate Estimation: The web interface automatically counts symbol
+    transitions in the buffer to approximate the baud rate and duty cycle
+    of the captured fob.
+
+    Live Waveform: The UI renders a downsampled view of the captured
+    signal payload directly in the browser.
+
+    Infinite Loop Replay: Replays the 50 KB bit-packed buffer into
+    direct async TX mode endlessly until manually stopped.
 
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