Add Ehwrj clean-room live map

CONTRIBUTING.md

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+# Contributing
+
+Thanks for improving Ehwrj.
+
+## Ground Rules
+
+- Keep the project limited to the benign War Thunder local map companion scope.
+- Do not add clipboard listeners, startup persistence, PE/ZIP mutation, credential collection, or external network reporting.
+- Keep local API traffic restricted to loopback addresses.
+- Put reusable parsing, projection, and tracking logic in `Ehwrj.Core`.
+- Keep Avalonia UI, overlay windows, and platform interop in `Ehwrj.App`.
+- Add or update tests when parser, coordinate, or tracking behavior changes.
+
+## Local Workflow
+
+On Ubuntu, bootstrap dependencies and run the full verification/publish pipeline:
+
+```bash
+scripts/bootstrap-ubuntu.sh
+```
+
+For an already prepared environment:
+
+```bash
+dotnet restore Ehwrj.sln
+dotnet format Ehwrj.sln --no-restore --verify-no-changes --verbosity minimal
+dotnet build Ehwrj.sln -c Release
+dotnet run --project tests/Ehwrj.Tests/Ehwrj.Tests.csproj -c Release --no-build
+scripts/verify-safety.sh
+```
+
+To develop the UI without War Thunder:
+
+```bash
+scripts/run-local-api-stub.sh
+```
+
+To capture and replay a real local API session:
+
+```bash
+scripts/capture-local-api.sh captures/my-session
+scripts/validate-capture.sh captures/my-session
+scripts/run-local-api-stub.sh 8111 captures/my-session
+```
+
+To publish a Windows x64 build from Linux:
+
+```bash
+scripts/publish-win-x64.sh
+```
+
+## Review Checklist
+
+- Build succeeds with zero warnings.
+- Tests pass.
+- New network code is justified and loopback-only unless explicitly documented.
+- UI controls remain dense, readable, and focused on operating the map/overlay.
+- Security boundaries in `SECURITY.md` are preserved.