test: cover the radio queue rules, shade TX state, rolling codes and web command hold

Move the pieces of the radio TX path that don't need FreeRTOS or NVS out of
Somfy.cpp and Web.cpp so they build in the native test env: the TX job and
event types and job encoding (TxBuffer), the queue rules (TxQueuePolicy.h),
a shade's pending radio jobs (ShadeTxState), the next rolling code
(RollingCode.h) and the web command queue types (WebCommand.h).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/WebCommand.h

@@ -0,0 +1,51 @@
+#ifndef WEB_COMMAND_H
+#define WEB_COMMAND_H
+#include <stdint.h>
+#include "SomfyFrame.h"
+
+// Commands the web servers hand to the main loop (src/Web.cpp).  Kept free of
+// the web server and FreeRTOS so it can be unit tested on the PC
+// (pio test -e native).
+
+// Commands are queued by the async web server and drained by the main loop.
+// Big enough for Home Assistant firing a command at every shade at once.
+#define WEB_CMD_QUEUE_SIZE 32
+
+enum class web_cmd_t : uint8_t {
+    shade_command,      // moveToTarget or sendCommand
+    group_command,      // group sendCommand
+    tilt_command,       // moveToTiltTarget or sendTiltCommand
+    shade_repeat,       // shade sendCommand/repeatFrame
+    group_repeat,       // group sendCommand/repeatFrame
+    set_positions,      // set shade position directly
+    shade_sensor,       // shade sensor command
+    group_sensor,       // group sensor command
+    set_my_position,    // shade setMyPosition (position/tiltPosition)
+    unpair_shade,       // shade unpair (Prog) and clear paired flag
+};
+
+struct web_command_t {
+    web_cmd_t type;
+    uint8_t shadeId;
+    uint8_t groupId;
+    uint8_t target;         // 0-100 or 255 (none)
+    somfy_commands command;
+    int8_t repeat;
+    uint8_t stepSize;
+    int8_t position;        // for setPositions
+    int8_t tiltPosition;    // for setPositions/tilt
+    int8_t sunny;           // for sensor
+    int8_t windy;           // for sensor
+    bool wasPaired;         // for unpair, restored if the Prog can't be sent
+};
+
+// Only setting positions never goes on air.
+inline bool webCommandUsesRadio(web_cmd_t type) { return type != web_cmd_t::set_positions; }
+// Whether the command at the head of the queue waits for the radio.  The
+// client was already told it was accepted so it stays queued until the radio
+// has room rather than have the radio drop it.  While TX is suspended nothing
+// gets through anyway so nothing is held back then.
+inline bool holdWebCommand(web_cmd_t type, bool txSuspended, bool txHasRoom) {
+  return webCommandUsesRadio(type) && !txSuspended && !txHasRoom;
+}
+#endif