diff --git a/CLAUDE.md b/CLAUDE.md
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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## What this is
+
+Mission Planner is the ArduPilot Ground Control Station (GCS): a large C# / .NET Framework
+Windows Forms desktop application for configuring, flashing, planning missions for, and
+monitoring ArduPilot/PX4 vehicles over the MAVLink protocol. The same source also targets
+Android (Xamarin) and macOS/iOS via a cross-platform library build.
+
+## Build & run
+
+Building is **Windows + Visual Studio 2022 + MSBuild only**. There is no supported build on
+Linux/macOS (those platforms only *run* the prebuilt binaries via Mono). Do not expect to
+compile this repo in a Linux container.
+
+```bat
+git submodule update --init          :: required once; pulls ExtLibs/mono and others
+.nuget\nuget.exe restore MissionPlanner.sln
+msbuild -v:m -restore -t:Build -p:Configuration=Release MissionPlanner.sln
+```
+
+- The main app is built from **`MissionPlanner.sln`** → `MissionPlanner.csproj` (`net472`, `Exe`).
+- Output goes to **`bin\Release\net461\`** (or `bin\Debug\net461\`) — the `net461` folder name is
+  intentional (`AppendTargetFrameworkToOutputPath=false`), it is *not* a separate target.
+- `build.bat`, `build - debug.bat`, `build - Clean.bat` are the maintainer's local build scripts
+  (they also do appx packaging/signing/rsync — not needed for plain builds).
+- To import the exact VS workload/component set, use `vs2022.vsconfig` (or `vs2019`/`vs2026`).
+
+### Cross-platform library build (Android / Mac)
+
+`MissionPlannerLib.csproj` (`netstandard2.0`, `library`) recompiles the same sources with
+`DefineConstants=...;LIB`. Android packaging is done via `build - Lib.ps1` and
+`ExtLibs/Xamarin/Xamarin.Android`. See the `LIB` conditional-compilation note below — it is the
+single most important thing to understand before touching shared code.
+
+### CI
+
+GitHub Actions (`.github/workflows/main.yml` = "DotNet Build", plus `android.yml`, `mac.yml`)
+build on Windows with MSBuild. CI builds the solution and zips `bin/Release/net461`; tagging
+`beta` publishes a release.
+
+## Tests
+
+`MissionPlannerTests/` is an MSTest project (`MSTest.TestFramework` 2.2.10, `net472`) that
+references the main projects. Tests use `[TestClass]` / `[TestMethod]` and `Assert`.
+
+```bat
+:: build then run via the VS Test Explorer, or:
+vstest.console.exe bin\Release\net461\MissionPlannerTests.dll
+:: single test:
+vstest.console.exe MissionPlannerTests.dll /Tests:DetectBoardTest
+```
+
+Coverage is light and focused on pure logic (board detection, firmware parsing, downloads). CI
+build pipelines do not run the test suite (`test: off`). When adding tests, mirror the existing
+folder layout (`MissionPlannerTests/Utilities`, `/GCSViews`, ...).
+
+## Architecture (the big picture)
+
+The dependency flow is: **transport → protocol → vehicle state → UI**.
+
+- **`Program.cs`** — process entry point and crash/exception handling.
+- **`MainV2.cs`** — the main `Form` and central hub. It owns the active connection as the static
+  `MainV2.comPort` (a `MAVLinkInterface`), hosts the menu, and swaps the `GCSViews` screens in and
+  out of the main window. Most global state hangs off `MainV2`. This file is ~190 KB; navigate by
+  symbol, don't read top-to-bottom.
+- **`GCSViews/`** — the top-level screens the menu switches between: `FlightData` (HUD/telemetry/
+  map), `FlightPlanner` (waypoint/mission editor), `InitialSetup`, `ConfigurationView` (Config/
+  Tuning + the many `Config*.cs` sub-panels), `SITL`, `Help`.
+
+### Connection & telemetry stack (in `ExtLibs/`)
+
+- **`ExtLibs/Comms/`** — transport layer implementing `ICommsSerial`: `CommsSerialPort`,
+  `CommsTCP`, `CommsUDP`, `CommsBLE`, `CommsNTRIP`, etc. Pick a transport, hand it to the interface.
+- **`ExtLibs/Mavlink/` (`MAVLink.csproj`)** — the MAVLink protocol: generated message structs,
+  `MavlinkParse` (frame parse/serialize), CRC. Largely machine-generated.
+- **`ExtLibs/ArduPilot/Mavlink/`** — the live link logic:
+  - `MAVLinkInterface` (`: MAVLink, IMAVLinkInterface`) — reads/writes packets over a transport,
+    exposes high-level operations (get/set params, mission up/download, command_long, etc.).
+  - `MAVState` — represents a single connected vehicle (sysid/compid) and holds `cs`, its
+    `CurrentState`. `MAVList` tracks multiple vehicles on one link.
+  - `CurrentState` (`ExtLibs/ArduPilot/CurrentState.cs`) — the decoded, UI-facing telemetry model
+    (attitude, position, battery, mode...). Forms/controls bind to `MainV2.comPort.MAV.cs`.
+- **`ExtLibs/ArduPilot/`** — the vehicle/domain layer beyond telemetry: firmware
+  (`APFirmware`, `Firmwares`), geofences, `BoardDetect`, mission packing.
+
+### Other notable `ExtLibs/` (each is its own csproj; there are ~90)
+
+`Controls/` (custom WinForms controls), `Core/` + `Interfaces/` (shared primitives, the
+`ServiceLocator` DI registry, `ICommsSerial`), `Maps/` + `GMap.NET.*` (mapping), `GDAL`/`ProjNet`/
+`SharpKml` (geo/projection/KML), `DroneCAN`/`UAVCANFlasher`, `Comms`, plus many vendored DLLs.
+The solution has ~93 projects; treat `ExtLibs/` as the bulk of the real functionality.
+
+### Plugins & scripting
+
+- **`Plugin/`** (`Plugin` base class + `PluginLoader`) and **`Plugins/`** (built-in plugins plus
+  `exampleNN-*.cs` templates) — plugins are loaded at runtime to extend the UI/behavior.
+- **`Script.cs` + `Scripts/`** — IronPython scripting host exposed to users (`cs`, `Script.*` API).
+
+## Conventions & gotchas
+
+- **`LIB` conditional compilation is the #1 trap.** Shared code is compiled both into the desktop
+  `Exe` (full `System.Drawing` / `System.Windows.Forms`) and into the netstandard `LIB` build for
+  Android/Mac. You will see `extern alias Drawing;` guarded by `#if !LIB`, and `ZZZLibShims.cs`
+  provides cross-platform shims (e.g. `MissionPlanner.Drawing`) for the `LIB` build. When adding
+  code that touches drawing, WinForms, P/Invoke, or other desktop-only APIs, guard it with
+  `#if !LIB` or it will break the Android/Mac build.
+- **Localization.** Each Form has an English `Name.resx` (the source of truth) plus per-culture
+  siblings like `FlightData.ko-KR.resx`, `MainV2.zh-Hans.resx`. App strings go through `Strings.resx`
+  / the `L10N` class (`Strings.Culture` is set from the `language` setting). Translations are
+  managed via Crowdin (`crowdin.bat`) — **do not hand-edit the non-English `.resx`**; edit the
+  English resource and let translation flow back.
+- **WinForms file triplets.** A screen is `Foo.cs` (logic) + `Foo.Designer.cs` (generated layout) +
+  `Foo.resx` (embedded resources). Edit the `Designer.cs` through intent, not by hand where possible.
+- **`createproj.bat`** regenerates the `<Compile>`/`<EmbeddedResource>` item lists for the csproj by
+  scanning the tree — useful when files are added/removed but kept out of sync with the project.
+- **`ServiceLocator`** (`ExtLibs/Interfaces/ServiceLocator.cs`) is the lightweight DI used to inject
+  platform-specific implementations (resolve with `ServiceLocator.Get<T>()`).
+- **`.editorconfig`** intentionally downgrades many `CAxxxx` analyzer rules to suggestion/silent —
+  don't treat those as actionable warnings.
+- **`Resources/`** holds icons/images; themes are `*.mpsystheme` files driven by `ThemeManager.cs`.
diff --git a/appveyor.yml b/appveyor.yml
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index 65de9fbb5d..0000000000
--- a/appveyor.yml
+++ /dev/null
@@ -1,55 +0,0 @@
-version: 1.0.{build}
-image: Visual Studio 2019
-configuration: Release
-clone_folder: c:\MP\
-build_script:
-- cmd: >-
-    git config -f .gitmodules submodule.mono.shallow true
-
-    git submodule update --init --depth 2 --no-single-branch 
-
-    dotnet --info
-
-    msbuild -v:m -restore /m -t:Build -p:Configuration=Release MissionPlanner.sln /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll"
-    
-    dir c:\mp\bin\Release\net461
-
-    cd bin\Release\net461
-    
-    powershell -command "ls plugins -recurse | ForEach-Object { if (Test-Path ($_.fullname -replace '\\plugins\\','\') -PathType Leaf) { $_.fullname }} | ForEach-Object { del $_ }"
-
-    copy version.txt c:\mp\
-    
-    rem del gdal dlls /s /f /q
-
-    7z a -tzip ..\..\..\MissionPlannerBeta.zip *
-
-    cd ..
-
-    md5sum.exe net461 > checksums.txt
-
-    copy checksums.txt c:\mp\
-
-    cd c:\mp\
-
-    cd msi 
-
-    rem wix.exe ..\bin\release\net461\ 
-
-    rem "%wix%\bin\candle" installer.wxs -ext WiXNetFxExtension -ext WixDifxAppExtension -ext WixUIExtension.dll -ext WixUtilExtension -ext WixIisExtension 
-  
-    rem "%wix%\bin\light" installer.wixobj "%wix%\bin\difxapp_x86.wixlib" -sval -o MissionPlanner-latest.msi -ext WiXNetFxExtension -ext WixDifxAppExtension -ext WixUIExtension.dll -ext WixUtilExtension -ext WixIisExtension 
-
-test: off
-artifacts:
-- path: MissionPlannerCov-int.zip
-- path: MissionPlannerBeta.zip
-- path: checksums.txt
-- path: version.txt
-- path: ChangeLog.txt
-deploy: off
-notifications:
-- provider: GitHubPullRequest
-  on_build_success: true
-  on_build_failure: true
-  on_build_status_changed: false
diff --git a/azure-pipelines.yml b/azure-pipelines.yml
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--- a/azure-pipelines.yml
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-# .NET Desktop
-# Build and run tests for .NET Desktop or Windows classic desktop solutions.
-# Add steps that publish symbols, save build artifacts, and more:
-# https://docs.microsoft.com/azure/devops/pipelines/apps/windows/dot-net
-
-trigger:
-- master
-- refs/tags/beta
-
-pool:
-  vmImage: 'windows-latest'
-
-variables:
-  solution: '**/MissionPlanner.sln'
-  buildPlatform: 'Any CPU'
-  buildConfiguration: 'Release'
-
-steps:
-- script: date /t
-  displayName: Get the date
-- script: dir /s
-  workingDirectory: $(Agent.BuildDirectory)
-  displayName: List contents of a folder
-
-- script: dotnet nuget locals all --clear
-- script: git submodule update --init --depth 2 --no-single-branch 
-
-- task: UseDotNet@2
-  displayName: Use .NET 6.0
-  inputs:
-    packageType: 'sdk'
-    version: '6.0.x'
-
-- task: VSBuild@1
-  inputs:
-    solution: '$(solution)'
-    platform: '$(buildPlatform)'
-    configuration: '$(buildConfiguration)'
-    msbuildArgs: '-restore /m'
-    logFileVerbosity: minimal
-
-- script: dir
-  workingDirectory: '$(Build.BinariesDirectory)' 
-  displayName: List contents of a folder
-
-- task: ArchiveFiles@2
-  inputs:
-    rootFolderOrFile: '$(Build.Repository.LocalPath)/bin/Release/net461' 
-    includeRootFolder: false
-    archiveFile: '$(Build.ArtifactStagingDirectory)/MissionPlanner.zip' 
-
-- task: PublishPipelineArtifact@0
-  inputs:
-    artifactName: 'MissionPlanner' 
-    targetPath: '$(Build.ArtifactStagingDirectory)/MissionPlanner.zip'
-    
\ No newline at end of file