Cleanup READMED and release notes

.claude/CLAUDE.md

@@ -320,3 +320,31 @@ cd3b462 ignore local
 - src/VictronBLE.h
 - src/crypto/vble_aes.c
 
+
+### Session: 2026-06-04 23:58
+**Commits:**
+```
+53fa6fa ignore pka file
+de6607d Branch version ready for testing with nRF52
+```
+**Modified files:**
+- .gitignore
+- README.md
+- UPGRADE_V0.4.md
+- VERSIONS
+- library.json
+- library.properties
+
+
+### Session: 2026-06-05 00:00
+**Commits:**
+```
+53fa6fa ignore pka file
+de6607d Branch version ready for testing with nRF52
+```
+**Modified files:**
+- .claude/CLAUDE.md
+- .gitignore
+- README.md
+- UPGRADE_V0.4.md
+

README.md

@@ -2,9 +2,7 @@
 
 A portable Arduino library for reading Victron Energy device data via Bluetooth Low Energy (BLE) advertisements — runs on both **ESP32** and **nRF52840**.
 
-**⚠️ API CHANGE in v0.4 — not backwards compatible with v0.3.x**
+v0.6 adds **multi-platform support** (ESP32 + nRF52840) via a hardware-abstracted BLE backend and dependency-free bundled crypto. (v0.5 brought the decoding accuracy fixes and AC charger support; v0.4 reworked the internals — function-pointer callback API, reduced memory usage, non-blocking scanning.) See [VERSIONS](VERSIONS) for full details. A stable **v1.0** release with a consistent, long-term API is coming soon.
-
-v0.4 is a major rework of the library internals: new callback API, reduced memory usage, non-blocking scanning. See [VERSIONS](VERSIONS) for full details. A stable **v1.0** release with a consistent, long-term API is coming soon.
 
 ---
 

UPGRADE_V0.4.md

@@ -1,106 +0,0 @@
-# Upgrading to VictronBLE v0.4
-
-v0.4 is a breaking API change that simplifies the library significantly.
-
-## Summary of Changes
-
-- **Callback**: Virtual class → function pointer
-- **Data access**: Inheritance → tagged union (`VictronDevice` with `solar`, `battery`, `inverter`, `dcdc` members)
-- **Strings**: Arduino `String` → fixed `char[]` arrays
-- **Memory**: `std::map` + heap allocation → fixed array, zero dynamic allocation
-- **Removed**: `getLastError()`, `removeDevice()`, `getDevicesByType()`, per-type getter methods, `VictronDeviceConfig` struct, `VictronDeviceCallback` class
-- **Removed field**: `panelVoltage` (was unreliably derived from `panelPower / batteryCurrent`)
-
-## Migration Guide
-
-### 1. Callback: class → function pointer
-
-**Before (v0.3):**
-```cpp
-class MyCallback : public VictronDeviceCallback {
-    void onSolarChargerData(const SolarChargerData& data) override {
-        Serial.println(data.deviceName + ": " + String(data.panelPower) + "W");
-    }
-    void onBatteryMonitorData(const BatteryMonitorData& data) override {
-        Serial.println("SOC: " + String(data.soc) + "%");
-    }
-};
-MyCallback callback;
-victron.setCallback(&callback);
-```
-
-**After (v0.4):**
-```cpp
-void onVictronData(const VictronDevice* dev) {
-    switch (dev->deviceType) {
-        case DEVICE_TYPE_SOLAR_CHARGER:
-            Serial.printf("%s: %.0fW\n", dev->name, dev->solar.panelPower);
-            break;
-        case DEVICE_TYPE_BATTERY_MONITOR:
-            Serial.printf("SOC: %.1f%%\n", dev->battery.soc);
-            break;
-    }
-}
-victron.setCallback(onVictronData);
-```
-
-### 2. Data field access
-
-Fields moved from flat `SolarChargerData` etc. into the `VictronDevice` tagged union:
-
-| Old (v0.3) | New (v0.4) |
-|---|---|
-| `data.deviceName` | `dev->name` (char[32]) |
-| `data.macAddress` | `dev->mac` (char[13]) |
-| `data.rssi` | `dev->rssi` |
-| `data.lastUpdate` | `dev->lastUpdate` |
-| `data.batteryVoltage` | `dev->solar.batteryVoltage` |
-| `data.batteryCurrent` | `dev->solar.batteryCurrent` |
-| `data.panelPower` | `dev->solar.panelPower` |
-| `data.yieldToday` | `dev->solar.yieldToday` |
-| `data.loadCurrent` | `dev->solar.loadCurrent` |
-| `data.chargeState` | `dev->solar.chargeState` (uint8_t, was enum) |
-| `data.panelVoltage` | **Removed** - see below |
-
-### 3. panelVoltage removed
-
-`panelVoltage` was a derived value (`panelPower / batteryCurrent`) that was unreliable (division by zero when no current, inaccurate due to MPPT conversion). It has been removed.
-
-If you need an estimate:
-```cpp
-float panelVoltage = (dev->solar.batteryCurrent > 0.1f)
-    ? dev->solar.panelPower / dev->solar.batteryCurrent
-    : 0.0f;
-```
-
-### 4. getLastError() removed
-
-Debug output now goes directly to Serial when `setDebug(true)` is enabled. Remove any `getLastError()` calls.
-
-**Before:**
-```cpp
-if (!victron.begin(2)) {
-    Serial.println(victron.getLastError());
-}
-```
-
-**After:**
-```cpp
-if (!victron.begin(2)) {
-    Serial.println("Failed to initialize VictronBLE!");
-}
-```
-
-### 5. String types
-
-Device name and MAC are now `char[]` instead of Arduino `String`. Use `Serial.printf()` or `String(dev->name)` if you need a String object.
-
-### 6. addDevice() parameters
-
-Parameters changed from `String` to `const char*`. Existing string literals work unchanged. `VictronDeviceConfig` struct is no longer needed.
-
-```cpp
-// Both v0.3 and v0.4 - string literals work the same
-victron.addDevice("MySolar", "f69dfcce55eb",
-    "bf25c098c156afd6a180157b8a3ab1fb", DEVICE_TYPE_SOLAR_CHARGER);
-```