docs: state current behaviour, drop change-log wording

Refs #3902

docs/agent-lifecycle/persistence.md

@@ -52,11 +52,10 @@ power-intent registry:
 - `kv` — small persistent key/value store (`key PK / value`) for
   host-side bookkeeping that doesn't warrant its own table.
 
-  ⚠️ The `mcp__hyperhive__remind` queue is **not** here any more: it
-  moved to a harness-local, per-agent store as part of the
-  loose-ends-v2 migration — see [`/harness/` contents
+  ⚠️ The `mcp__hyperhive__remind` queue lives in a harness-local,
+  per-agent store — see [`/harness/` contents
   below](#state-dirs-per-agent) for where reminders (and todos)
-  actually live now.
+  live.
 - `approvals` — the queue. `agent / kind (merge_config_pr | spawn |
   update_meta_inputs | schedule_prompt) /
   commit_ref / requested_at / status / resolved_at / note`.
@@ -109,11 +108,11 @@ One table:
   harness emits during turn loop execution.
 
 <!-- vale write-good.Passive = NO -->
-The harness both writes and vacuums it — this used to be a host-side
-sweep, but hive-c0re runs as the unprivileged `hive-core` user under
+The harness both writes and vacuums it. Cleanup runs in-container
+because hive-c0re runs as the unprivileged `hive-core` user under
 privsep and can't delete agent-owned files (host-side deletes hit
 `PermissionDenied` on the bash-task trio and a readonly database error
-here), so cleanup moved in-container. `hive-agent`'s `vacuum::run`
+here). `hive-agent`'s `vacuum::run`
 (`hive-agent/src/vacuum.rs`) sweeps hourly. Retention is
 **type-scoped**: it deletes only the verbose `stream` rows (the raw
 claude `stream-json` deltas — one per text chunk / tool use, the bulk
@@ -192,10 +191,9 @@ is in-process only, so it wouldn't serialise a writer running as a
 separate process; none of today's writers are.
 
 hive-c0re reads this file on each `build_all` sweep (~10s) via
-`container_view::read_harness_flags`. Falls back to the legacy individual
-sentinel files (`hyperhive-rate-limited`, `hyperhive-needs-login`) if the
-JSON is absent, so existing containers keep working through the transition
-window before their next rebuild.
+`container_view::read_harness_flags`. Falls back to the individual
+sentinel files (`hyperhive-rate-limited`, `hyperhive-needs-login`) when the
+JSON is absent.
 
 ### `/var/lib/hyperhive/db/build_logs.sqlite` (host)
 
@@ -218,7 +216,7 @@ Three indices:
 - `(node_id)` — added by a later migration so a build log row can be
   looked up by the job-queue node it belongs to (a `hive_jobq` node is
   immutable after insert, so hive-c0re records the link on the log row
-  instead); legacy rows predating the column keep `node_id IS NULL`.
+  instead); rows predating the column have `node_id IS NULL`.
 
 Writes are best-effort: `append_stdout` / `append_stderr` / `finish`
 log a warning on sqlite error and let the build continue. A failed
@@ -293,22 +291,19 @@ Under `/var/lib/hyperhive/agents/<name>/`:
     (`hive-agent`'s `vacuum::run`, same one that ages out `stream`
     event rows above) deletes terminal task trios older than 48
     hours; non-terminal (still-running) tasks are never deleted. This
-    used to be a host-side `hive-c0re` vacuum, moved in-container for
-    the same privsep-ownership reason as the events vacuum above.
+    sweep runs in-container, for the same privsep-ownership reason as
+    the events vacuum above.
   - `hyperhive-state.sqlite` — consolidated loose-ends-v2 store: todos
     and reminders, one small table each in a single file (in-container
     daemons — `hive-bash-daemon`, `hive-matrix-daemon`,
     `hive-forge-notify` — upsert keyed todos here over the harness's
     in-agent socket, `HIVE_AGENT_SOCKET`; the harness merges them into
     `get_loose_ends` output and clears a row on `mark_todo_done`).
-    Replaces three formerly separate files
-    (`hyperhive-todos.sqlite`, `hyperhive-reminders.sqlite`, and the
-    old file-based `mcp-loose-ends/` scanner before that) — a one-time
-    boot migration (`db_migrate::run`) folds the legacy files into this
-    path the first time a harness boots after the upgrade. Also backs
-    the `mcp__hyperhive__remind` queue, which moved from a host-side
-    `broker.sqlite` table to this per-agent store as part of the same
-    migration.
+    Consolidates todos and reminders into one file. A one-time boot
+    migration (`db_migrate::run`) folds any pre-existing files
+    (`hyperhive-todos.sqlite`, `hyperhive-reminders.sqlite`, the older
+    file-based `mcp-loose-ends/` scanner) into this path the first time
+    a harness boots. Also backs the `mcp__hyperhive__remind` queue.
 
     The harness itself is also a producer, not just the socket server:
     boot wiring's `spawn_todo_socket` starts `todo_server::run` (the
@@ -344,9 +339,7 @@ The RW on `state` is deliberate, not an oversight: the holder recovers
 other agents, which includes writing into their state (for example
 seeding notes, clearing a stuck sentinel) as well as reading it.
 
-This is the **only** cross-agent mount. Dropping the topology parent
-field took with it the unconditional grant every agent used to
-get over its own direct children — an agent holding no capability now
+This is the **only** cross-agent mount. An agent holding no capability
 sees its own dirs and nothing else.
 
 **`harness` isn't mounted at all.** It holds that agent's own runtime
@@ -395,8 +388,8 @@ Contents:
 - `topology.json` — the agent roster (`["alice", "bob", "ruth"]`).
   Written by `topology::reconcile` on every meta sync; read by
   `topology::all_agents`, which is the set the `ManageRootAgent`
-  capability grants mounts over. Carried a `parent` per agent in the
-  legacy format; the reader still accepts that shape and keeps its keys.
+  capability grants mounts over. The reader also accepts a map-shaped
+  file carrying a `parent` per agent, and keeps its keys.
 - `tool-groups.json` — per-agent MCP tool group grants
   (`{ "alice": ["messaging", "inbox", "execution"] }`). Written by
   `tool_groups::set_groups`; injected as `HIVE_TOOL_GROUPS` env
@@ -420,9 +413,8 @@ Contents:
 
 The root agent has the meta dir RO-mounted at `/meta/`.
 
-The `.meta-migration-done` marker no longer exists: the
-one-shot container repoint it guarded no longer exists either, since
-hive-c0re renders containers onto `meta#<n>` at creation. A stale
+hive-c0re renders containers onto `meta#<n>` at creation, so there is
+no `.meta-migration-done` marker to guard a one-shot repoint. A stale
 marker file left over from an older hive is inert and the operator can
 delete it.
 
@@ -519,7 +511,7 @@ reinstall.
 
 The harness runs as a per-agent unix user inside the container
 (`services.hyperhive.agent.user.name`, defaults to the agent's logical label so each
-container has a uniquely named user). Operators with legacy root-owned
+container has a uniquely named user). Operators with root-owned
 state dirs need a one-time data shuffle so they don't lose their claude
 session.
 
@@ -533,8 +525,7 @@ container lifetime:
    chance to chown. Also re-applies on every rebuild in case the
    meta-flake's per-agent name evolves (rare).
 2. **Migrate any leftover `/root/.claude` content into
-   `${homeDir}/.claude`** — legacy `claude` wrote to root's
-   empty home; the bind mount didn't exist yet. Marker
+   `${homeDir}/.claude`.** Marker
    (`/var/lib/hive-agent-user-migrated`) guards single-shot; it's
    only written once there's nothing left to migrate, so a `cp`
    failure leaves it absent and the next boot retries.
@@ -557,9 +548,7 @@ container lifetime:
    there as the agent user. Why the mode matters:
    [`boundary.md`](../trust-boundary/boundary.md#the-per-agent-socket-dir).
 
-The activation script will eventually become unnecessary once no
-operators have legacy root-owned state dirs left to migrate; drop
-the body + marker check at that point.
+The activation script migrates any root-owned state dir still present.
 
 ## Matrix per-agent daemon + token-arrival trigger