docs: drop statements about absent things, state current behaviour

docs/integrations/matrix.md

@@ -207,17 +207,14 @@ tuwunel has none.
 Promoting a user to homeserver admin and resetting a password both need an
 admin **sender**: `!admin …` messages into `#admins:<server_name>`, and
 tuwunel only treats a message as a command when its sender is already an
-admin. `@hive-<hive>:` has no admin sender to make that call with. Both are
-swarm-level operations.
+admin. Only `@swarm` is a homeserver admin, so both are swarm-level
+operations.
 
 <details><summary>Store precedence for a hive's sender account</summary>
 
-`swarm/services/matrix/sender-token` is a shared path `hive-c0re` and
-`swarm-controller` both build from the same function; nothing reads it.
 `ensure_hive_user` reads the per-hive path
 `swarm/hives/<hive>/matrix/sender-token` **first, on every sweep**, not
-just when that file is missing (`sender_source`'s decision), so a value
-at the shared path never takes effect once the per-hive path has one.
+just when that file is missing (`sender_source`'s decision).
 `swarm-controller` mints a per-hive token within five minutes of a hive
 appearing; the sweep then overwrites the per-hive file, no boot
 required.
@@ -246,9 +243,7 @@ halves. `registrationTokenFile` is a removed option: a config that
 still sets it fails to evaluate with a message naming the appservice.
 
 <!-- vale write-good.Passive = NO -->
-- **Access tokens are independent of the registration token.** An
-  access token lives on the device that minted it, so accounts and
-  sessions are unaffected by the registration token's presence.
+- **Access tokens live on the device that minted them.**
   `login_with_password` stays on, so the password fallback works
   too.
 - **The homeserver's `admin_execute` promotes only `@swarm` at boot**
@@ -271,9 +266,9 @@ Initial rollout settings:
   until you list peers.
 - `allow_registration = false`. tuwunel checks this flag only for
   requests that arrive **without** an appservice token, so the appservices
-  still create accounts and tuwunel refuses everyone else. It's not a
-  hardening afterthought: with no registration token configured,
-  `allow_registration = true` makes tuwunel refuse to start unless
+  still create accounts and tuwunel refuses everyone else. With no
+  registration token configured, `allow_registration = true` makes
+  tuwunel refuse to start unless
   `yes_i_am_very_very_sure_…_open_registration_…` is also set.
 - `allow_encryption` — server-side E2EE switch, sourced from
   `services.hyperhive.swarm.matrix.allowEncryption` (**default `false`**, opt-in).