Native crash capture on Windows, and startup steps in crash reports (#1215)

A crash inside a graphics driver left only "an unclean exit between
commands": no backtrace, no module, no hint that it was at startup.

- The crash journal now keeps the startup step the app is in (window,
  graphics instance, surface, adapter request, adapter chosen, device
  creation, renderer and viewport shader compiles, surface configure,
  first frame and its present, running) and the renderer as soon as the
  adapter is picked. egui-wgpu tells the app about its steps through a
  small hook. An unclean exit before the first frame names the step.
- Windows: an unhandled-exception filter (src/native_crash.rs, the one
  Windows-only module allowed unsafe) writes the exception code, the
  faulting module and offset, and a minidump next to the journal; the
  next start puts them into the report.
- The Windows CI job runs a child that faults on purpose and checks the
  report.

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

.github/workflows/ci.yml

@@ -328,7 +328,7 @@ jobs:
         with:
           key: windows-startup
       - name: Backend order and probing on Windows
-        run: cargo test -p solidcraft --profile ci --locked -- startup::tests
+        run: cargo test -p solidcraft --profile ci --locked -- startup::tests native_crash::tests
       - name: Build the app
         run: cargo build -p solidcraft --profile ci --locked
       - name: Start the app under different settings