docs: record cross-platform validation evidence

blueprint/context/current-feature.md

@@ -191,14 +191,25 @@ Build one step at a time, never the whole feature at once.
   cover both choices, EOF or cancelled input, noninteractive behavior, and an
   already-running instance; the prompt itself contains only the two requested
   run modes.
-- [ ] **Step 8 - Document and prove all three platforms** - update README usage
+- [x] **Step 8 - Document and prove all three platforms** - update README usage
   and limitations, remove stale Restart wording, run the full Rust and frontend
   gates, and require the Ubuntu, macOS, and Windows CI matrix. Record live
   foreground, start, status, stop, sign-in startup, and disable evidence from
   each operating system before completion. *Done when:* `cargo fmt --check`,
   `cargo test`, `cargo clippy -- -D warnings`, `npm run lint`, and
   `npm run build` pass; all three CI operating systems pass; the manual lifecycle
-  matrix has no unresolved failure.
+  matrix has no unresolved failure, or Brad explicitly accepts any recorded
+  verification gaps.
+  *Accepted evidence (2026-07-27):* all local gates passed, and both push and
+  pull-request CI passed on Ubuntu, macOS, and Windows. Live Linux foreground,
+  background start, status, terminal detachment, stop, and disable passed. Brad
+  reported the macOS foreground and background lifecycle working correctly.
+  The Windows source build stopped before compiling PortDoc because that
+  machine's active GNU Rust toolchain lacked `dlltool`; native Windows CI passed
+  the feature tests and strict Clippy. Sign-in startup was not manually tested
+  on any platform. Brad accepted the Windows live-test and sign-in-test gaps and
+  approved proceeding on the automated and available live evidence. These are
+  accepted verification gaps, not passing manual evidence.
 
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