publish supply-chain gate plan, honest status section in README

RAF/SUPPLY_CHAIN_GATE_PLAN.md unblocked — the architectural thesis for the
capability-token model. Updated to reflect agent-self upgrade path, OSV
expansion, and current verification state.

README Status section rewritten: "implemented and locally exercised, not
production-proven" replaces the misleading "working in production" header.
Honest gaps listed (GATE-002, CRITICAL-004).

README.md

@@ -141,7 +141,9 @@ Before a package is installed: the agent fetches the expected SHA-256 from the s
 
 ## Status
 
-**Working in production:**
+**Compiles, runs on the maintainer's stack, not yet battle-tested.** No live deployment outside the dev environment. The gate (supply-chain verification) has not completed a full end-to-end run against real infrastructure. Treat everything below as "implemented and locally exercised, not production-proven."
+
+**Implemented:**
 - Linux and Windows agent registration and update management
 - APT, DNF, Winget, Windows Update, Docker image scanning
 - Dry-run dependency checking
@@ -150,14 +152,14 @@ Before a package is installed: the agent fetches the expected SHA-256 from the s
 - Supply chain hash verification and OSV.dev checks
 - Maintenance windows
 - Upstream version tracking (GitHub, Gitea, GitLab, Bitbucket, Repology, endoflife.date)
-- Agent self-update with rollback
+- Agent self-update via privileged helper (zero agent sudo)
 
-**Known issues:**
-- Winget detection occasionally misses packages (Windows API limitation)
-- Some Windows Updates reappear after installation (Windows Update quirk, not ours)
-- No AUR, Snap, Flatpak, or Homebrew support yet
-- macOS agent binaries not yet signed
-- Mobile dashboard is usable, not optimized
+**Not yet done:**
+- Live end-to-end gate test (GATE-002)
+- Windows installer stubs report fake success (CRITICAL-004)
+- No AUR, Snap, Flatpak, or Homebrew support
+- macOS agent binaries not signed
+- Mobile dashboard usable, not optimized
 
 ---