README: add SD card commands, project structure, doc links

Co-authored-by: Cursor <cursoragent@cursor.com>

README.md

@@ -136,6 +136,14 @@ iperf status
 - `monitor channel <channel>` - Set monitor channel
 - `monitor status` - Show monitor status
 
+### SD Card Commands
+- `sdcard status` - Show CD, mounted, capacity, fiwi-telemetry info
+- `sdcard list [path]` - List files (path optional, default root)
+- `sdcard write <file> <text>` - Write text to file
+- `sdcard read <file>` - Read and print file
+- `sdcard send <file>` - Stream file over serial (use tools/sdcard_recv.py)
+- `sdcard delete <file>` - Delete a file
+
 For detailed command documentation, see [Quick Reference](doc/QUICK_REFERENCE.md).
 
 ## Mass Deployment
@@ -192,15 +200,24 @@ The deployment script (`esp32_deploy.py`) can use these stable symlinks when `--
 ```
 ├── main/                  # Main application code
 │   ├── main.c            # Entry point and console initialization
+│   ├── broadcast_beacon.c/h  # UDP broadcast for laptop discovery
 │   └── board_config.h    # Hardware pin definitions
 ├── components/
-│   ├── app_console/      # Console command implementations
+│   ├── app_console/      # Console command implementations (cmd_*)
 │   ├── iperf/            # iPerf traffic generator core
 │   ├── wifi_controller/  # WiFi management and monitor mode
+│   ├── wifi_monitor/     # 802.11 frame capture and collapse detection
 │   ├── wifi_cfg/         # WiFi and IP configuration storage
 │   ├── gps_sync/         # GPS PPS and NMEA parsing
 │   ├── status_led/       # LED status indication
-│   └── ...
+│   ├── sd_card/          # SD card SPI mount and file I/O
+│   ├── sdcard_http/      # HTTP server for SD file download (port 8080)
+│   ├── mcs_telemetry/    # MCS/RSSI telemetry -> fiwi-telemetry
+│   ├── csi_log/          # CSI logging (when CSI enabled)
+│   └── csi_manager/      # CSI configuration (when CSI enabled)
+├── tools/
+│   ├── beacon_listen.py  # Listen for beacons, download fiwi-telemetry
+│   └── sdcard_recv.py    # Receive file over serial from device
 ├── esp32_deploy.py       # Mass deployment script
 ├── gen_udev_rules.py     # USB port mapping utility
 └── doc/                  # Additional documentation
@@ -210,6 +227,8 @@ The deployment script (`esp32_deploy.py`) can use these stable symlinks when `--
 
 - [Quick Start Guide](doc/QUICK_START.md)
 - [Quick Reference](doc/QUICK_REFERENCE.md)
+- [SD Card Wiring](doc/SD_CARD_WIRING.md) - Hardware, file transfer, beacon discovery
+- [Telemetry Capture](doc/TELEMETRY_CAPTURE.md) - Enable and capture fiwi-telemetry
 - [Deployment Guide](doc/DEPLOYMENT_GUIDE.md)
 - [Mass Deployment](doc/MASS_DEPLOY.md)
 - [GDB Debugging Guide (ESP32-C5)](doc/ESP32-C5_GDB_Debugging_Guide.md)