v0.2.9.3: device classification + ARM support — Pixel 3 lands

DEVICE-002: ARM machine-ID fallback — device-tree model + /etc/machine-id
combo, then /proc/cpuinfo Serial (all-zero rejected), before the weak
hostname fallback. Hardware-bound IDs on DMI-less devices.

DEVICE-001: agent detects device_type (server/desktop/phone/tablet) from
/sys signals — system battery (scope=Device peripherals excluded, UPS
excluded), DRM connector state, framebuffer min-dimension for phone/tablet
split. Reports device_type/device_model/os_distro in registration and
system-info paths.

SERVER-001: migration 061 — device_type, device_type_manual (operator
override, never agent-written), device_model, os_distro on agents.
effective_device_type computed into every serialized agent.

SERVER-002: PUT /admin/agents/:id/device-type — set/clear override,
enum-validated, journaled.

WEB-001: device-type icons + fleet filter, device model in list, detail
header badge with reclassify dropdown, os_distro surfaced.

INSTALL-003: arm64 install path unblocked — helper (required manifest
component) now cross-built aarch64-unknown-linux-musl via rust-lld in the
server image, signed at boot (helperArches += arm64), listed in the release
manifest. Install template already handled uname -m and pacman.

Plus in-flight: desktop tray wiring, enrollment page polish, CI workflow
updates, RAF session-broker/pacman-scanner docs, native installer scaffold.

RAF/OVERVIEW.md

@@ -1,6 +1,6 @@
 # Start Here: RedFlag Architecture Overview
 
-**Version:** v0.2.8.0 (June 2026)
+**Version:** v0.2.9.3 (July 2026)
 
 This is the entry point into the RedFlag Architecture Framework. Read this first to
 understand the shape of the system, then follow the links into the detailed docs.
@@ -56,6 +56,28 @@ paths cannot drift on what counts as a clean closure.
   load-bearing constraints, enforcement layers, trust chain, hash registry
 - `docs/tasks/GATE-000-supply-chain-gate-plan.md` — build status & implementation tracking (not design)
 
+### Tier 3: Break-Glass Sessions
+
+When Tiers 1–3 (read, catalog actions, signed runbooks) can't cover the case — live
+shell, desktop control, or an urgent pre-signed runbook triggered by detection — the
+session broker provides a break-glass path. It is a **separate privileged Rust binary**
+(`redflag-broker`), spawned on demand via the same `sudo systemd-run` pattern as the
+helper, disposable, time-boxed, and audit-logged.
+
+The broker cannot start without a minted, Ed25519-signed session grant specifying
+exactly what it may do. The agent verifies the grant and spawns the broker; after that
+the agent is out of the loop. The broker opens its own connection to the server, streams
+live I/O, hash-chains every command in a tamper-evident audit log, and exits when the
+grant expires.
+
+**Prerequisite:** Tier 4 requires RBAC (operator-level role gating for grant minting).
+The design is complete but gated behind the RBAC substrate — a break-glass path without
+role-gated minting is just "anyone can get a root shell."
+
+**Architecture docs:**
+- [components/06-session-broker](components/06-session-broker.md) — design of record: grant format,
+  trust chain, audit trail, sequence diagram, scope variants
+
 ### Process Explorer
 
 On-demand `/proc` filesystem scanning for process inventory and drill-down detail.
@@ -116,7 +138,7 @@ From `security/05-supply-chain-gate.md` — do not regress these:
 | Section | What It Describes |
 |---------|-------------------|
 | [core](core/) | ETHOS principles, architectural decisions |
-| [components](components/) | Server, agent, web, helper — package structure and responsibilities |
+| [components](components/) | Server, agent, web, helper, session broker — package structure and responsibilities |
 | [security](security/) | Trust boundaries, auth stack, machine binding, supply chain gate |
 | [verification](verification/) | Ed25519 signing pipeline, agent verification, key rotation, replay protection |
 | [scanners](scanners/) | Per-ecosystem scanner behavior and integration points (incl. process scanner) |