docs: fix bash-tasks retention + matrix provisioning daemon restart

persistence.md: bash-tasks/ says "persist until container purge" but
bash_tasks_vacuum now runs hourly and deletes terminal task trios older
than 48 hours. Update the description to reflect actual retention policy.

matrix.md: add step 6 to the Provisioning flow section documenting that
hive-c0re restarts hive-matrix-daemon immediately after writing the
access_token (fix for issue #1329). Previously the doc stopped at token
write; the restart + .path-trigger fallback interplay was undocumented.

docs/persistence.md

@@ -188,8 +188,9 @@ Under `/var/lib/hyperhive/agents/<name>/`:
   - `bash-tasks/` — task JSON + stdout/stderr files for
     background `mcp__bash__run` jobs. JSON files are
     `<id>.json` (status + tails), `<id>.out` / `<id>.err`
-    (full captured output). Task files persist until container
-    purge.
+    (full captured output). `hive-c0re::bash_tasks_vacuum` runs
+    hourly and deletes terminal task trios older than 48 hours;
+    non-terminal (still-running) tasks are never deleted by vacuum.
   - `mcp-loose-ends/` — JSON files published by external MCP daemons
     (e.g. `hive-bash-mcp`, `hive-matrix-mcp`) listing their active
     loose-end summary strings. Each file is `<daemon>.json` containing