Extend browser admin lifecycle actions

Support browser reboot and HTTPS stop through deferred control, plus
exact
`web certificate rotate --force` handoff to the dispatcher. Add typed
request
validation and focused boundary and lifecycle coverage.

docs/phase8d_plan.md

@@ -1,6 +1,6 @@
 # Phase 8D — Incremental web administration plan
 
-Status: **8D.0–8D.5 and M1 validated by explicit user sign-off. 8D.6 implemented, host-tested and build-verified; target validation and independent parent review pending, no phase sign-off. 8D.5 closure on 2026-09-06 stands. Numeric reserve gates remain open. 8D.7–8D.22 remain planned, each requiring a separate implementation request.** See the [8D.6 implementation record](phase8d6_implementation.md), [8D.5 implementation record](phase8d5_implementation.md), [8D.4 implementation record](phase8d4_implementation.md), [8D.3 implementation record](phase8d3_implementation.md) and [8D.0 baseline/M1 contract](phase8d_baseline.md).
+Status: **8D.0–8D.6 and M1 validated by explicit user sign-off. 8D.7 first stop/reboot and second certificate slices implemented, host-tested, build-verified and reviewed; target validation and M2 acceptance pending. User explicitly authorized stacking the next bounded credential/account slice, not target sign-off. Other owner slices remain; 8D.8–8D.22 are not authorized by that continuation. Numeric reserve gates remain open.** See the [8D.6 implementation record](phase8d6_implementation.md), [8D.5 implementation record](phase8d5_implementation.md), [8D.4 implementation record](phase8d4_implementation.md), [8D.3 implementation record](phase8d3_implementation.md) and [8D.0 baseline/M1 contract](phase8d_baseline.md).
 
 This is the execution plan for [roadmap Phase 8D](roadmap.md#phase-8--role-based-users-and-administrative-access). The roadmap retains the feature/security requirements; this document defines small work units, dependencies, and release gates. The [administration test matrix](user_administration_tests.md#planned-phase-8d-integrated-web-administration) remains the final acceptance checklist.
 
@@ -138,11 +138,15 @@ If 8D.3 exceeds the work-unit limit, first split out inert login-page rendering
 
 ### 8D.7 — Web-shell lifecycle parity and M2 acceptance
 
+**Second bounded certificate slice:** [Implementation, separate slice histories and pending target checklist](phase8d7_implementation.md). Exact parsed browser `web certificate rotate --force` uses a typed request-queue union and immutable owner `dispatcher_actions` mask: bounded drain/200 ms then nonblocking handoff to the existing 12 KiB dispatcher, not 4 KiB control. Pending input gating, token/principal/session revalidation and executing-slot reservation persist through execution. Transactional certificate commit → stop → start short-circuits errors and retains ownership on failed stop; SSH/UART0 unchanged. No new tasks/depth/routes/assets/stacks; target owner-mask/local-scratch accounting and stack margins unknown, host sizeof is not proof. Parent final `pio run` PASS **26.32 s, 95,580 B RAM / 1,648,061 B flash**: **0 / +1,036 B** vs first slice, **0 / +1,572 B** vs 8D.6, **+1,048 / +48,088 B** vs 8D.0. Implementer focused suites pass (transport **25**/tickets **12**, server **11**, boundary including certificate, lifecycle/policy/cookie-admin/store-serial/diff); independent reviewer reports no actionable findings. Sanitizers unavailable (missing libasan/libubsan); no hardware validation. User explicitly authorized stacking the next bounded slice: credential/account, then other owner slices. Other mutations remain blocked; target/M2 acceptance and numeric reserves pending. This supersedes the first-slice next-step/continuation-pending statement below.
+
+**First bounded increment history (2026-09-06):** [Implementation, restrictions and target checklist](phase8d7_implementation.md). Browser `reboot` and `web stop` now use existing deferred control with final WEB session/currentness checks and discard of pending input. Other identity/network/account/SSH restrictions remain explicit. Host suites/review/build pass: **95,580 B RAM / 1,647,025 B flash**, **0 / +536 B** versus 8D.6, final build **12.44 s**. No new task/route/capacity. Target regression or explicit continuation decision pending; this is not completed 8D.7/M2. Next slice remains HTTPS identity/certificate handling, not settings. Prior sign-offs stand; numeric reserves remain open.
+
 **Start in:** The console deferred-control boundary, web lifecycle owner, and only the affected command handlers.
 
 **Scope:** Close the explicit 8D.5 restrictions for self-terminating web-shell operations (including HTTPS stop/identity changes and reboot where supported by the canonical registry). Reuse bounded deferred acknowledgement/close semantics; never claim application-buffer draining proves browser receipt. Prevent further input during pending actions. Preserve UART0-only bootstrap/recovery and safe policy for one-time self-generated credentials. No typed danger-zone API yet. If this requires several distinct owner changes, split them before implementation and keep unimplemented actions explicitly rejected.
 
-**Gate — M2 (mandatory target/browser pause):** Browser/UART0/admin-SSH commands serialize with no output or hidden-prompt crossover; queued work is discarded after logout/revocation/slot reuse. Deferred operations acknowledge or fail within bounds and reconnect behaves as documented. Run simultaneous USB, serial WebSocket, admin WebSocket, user SSH, admin SSH, UART0 and UART1 traffic; verify lease retention, recovery availability, and measured memory/stack floors. Web-admin initialization/admission failure must leave M1 serial login and existing non-web paths usable. Stop for user confirmation before settings.
+**Gate — M2 (mandatory target/browser pause):** Browser/UART0/admin-SSH commands serialize with no output or hidden-prompt crossover; queued work is discarded after logout/revocation/slot reuse. Deferred acknowledgement/drain handling is bounded and reconnect behaves as documented; this is not confirmed peer receipt or a deadline for dispatcher queue residence or underlying certificate/NVS/lifecycle execution. Run simultaneous USB, serial WebSocket, admin WebSocket, user SSH, admin SSH, UART0 and UART1 traffic; verify lease retention, recovery availability, and measured memory/stack floors. Web-admin initialization/admission failure must leave M1 serial login and existing non-web paths usable. Stop for user confirmation before settings.
 
 ## M3 — Typed settings, one domain per chunk
 
@@ -179,11 +183,11 @@ Update the roadmap and user/command documentation to distinguish completed featu
 
 ## Progress and next-request template
 
-Progress: **8D.0–8D.5 and M1 validated by user sign-off; numeric reserves remain open. 8D.6 implemented/host-tested/build-verified, target pending. 8D.7–8D.22 planned.** Record incremental results in `docs/agent/current-state.md`, retaining the [baseline](phase8d_baseline.md) and cumulative resource measurements as work proceeds. The baseline records user-provided evidence and sign-off; this does not imply completion of later browser-authentication acceptance checks.
+Progress: **8D.0–8D.6 and M1 validated by user sign-off; numeric reserves remain open. 8D.7 stop/reboot and certificate slices implemented/host-tested/build-verified/reviewed, target/M2 acceptance pending. User authorized the next bounded credential/account slice, then other owner slices; settings remain out of scope.** Record incremental results in `docs/agent/current-state.md`, retaining the [baseline](phase8d_baseline.md) and cumulative resource measurements as work proceeds. The baseline records user-provided evidence and sign-off; this does not imply completion of later browser-authentication acceptance checks.
 
 Suggested next request:
 
-> Review and target-validate Phase 8D.6 using its implementation checklist. Preserve the serial connection, broker identity and writer lease while switching terminals. Record actual browser/target results and open numeric reserve gates; do not implement 8D.7 lifecycle parity or settings without a separate request.
+> Continue the explicitly authorized next bounded 8D.7 credential/account slice. Preserve unsupported restrictions until safe owner handling exists, UART0-only bootstrap/recovery, secret-safe one-time credential policy and existing resource bounds. Use the second-certificate-slice handoff; do not treat continuation as target sign-off. Other owner slices and the full target/browser M2 acceptance checkpoint remain before settings.
 
 For later chunks: