docs: consolidate design change logs and refresh stale docs

docs/deployment.md

@@ -45,7 +45,7 @@ Once the restart helper is installed (it writes `update-helper.json` next to `DB
 
 The owner's Restart button installs a downloaded update, or just restarts the site, without touching the server by hand. The app itself stays unprivileged: the systemd unit below keeps `ProtectSystem=strict` and only the data directory (the directory that holds `DB_FILE`) is writable. The only privileged code is a small helper, the same binary started as `renewcms apply-update` by a systemd service that runs as root.
 
-First install v2.6.0-beta or newer manually, back up the database, uploads and current binary, and confirm the app runs as an unprivileged service user. The binary and its parent directory should be controlled by root. Owners can start updates and restarts; admins have read-only update status.
+First install the helper manually, back up the database, uploads and current binary, and confirm the app runs as an unprivileged service user. The binary and its parent directory should be controlled by root. Owners can start updates and restarts; admins have read-only update status.
 
 #### Find the actual database directory
 
@@ -121,7 +121,7 @@ On the latest release you can test only a plain restart. Test installation, forc
 - **Restart is missing:** reload Settings, confirm you are owner, and inspect `GET /v1/system/update` in the browser's Network panel. For an idle owner, `can_apply: false` means the app did not detect the helper. Check that `update-helper.json` is beside the actual database and readable by the service user.
 - **Wrong helper directory:** disable the helper with the old `--data-dir`, then enable it with the correct directory and port. Do not change `DB_FILE` to compensate.
 - **Overlay does not clear:** inspect the helper journal, `update-result.json` and `update-running.json` in the actual database directory. Check localhost health on the configured port, then public health through the proxy. Do not cache `/healthz` at the proxy.
-- **Old binary panics on `--version`:** older releases may interpret it as normal startup and require server environment variables. v2.6.0-beta and newer print their version without loading configuration. A separately launched process failing this way does not stop the systemd service.
+- **Old binary panics on `--version`:** releases before v2.6.0-beta treat it as normal startup and require server environment variables. A separately launched process failing this way does not stop the systemd service.
 - **Download or verification fails:** inspect the app journal. All assets and redirects must use HTTPS on the configured feed host. The release must include the six binaries, `checksums.txt` and `checksums.txt.sig`.
 - **Update rolls back:** check the previous version and helper journal. Automatic rollback restores the binary, not the database; schema changes still require a recovery plan.
 
@@ -159,7 +159,7 @@ What is supported and what is not:
 
 #### Verification status
 
-A real v2.6.0-beta plain browser restart was confirmed on Linux/systemd on 2026-10-02: the path unit triggered the helper, a new server process started, the result was `succeeded`, and public health returned `ok`. Real signed installation, forced rollback and adversarial filesystem checks remain unverified. The manual cases are listed in [the restart QA procedure](../features/updates_restart_helper.qa.md).
+Only the plain browser restart has been confirmed on a real Linux/systemd machine. Signed installation, forced rollback and adversarial filesystem checks remain unverified; the manual cases are in [the restart QA procedure](../features/updates_restart_helper.qa.md).
 
 ## 2. Lay out the server