New realism_config table (uuid PK + unique key) + two repo methods
(get/set) backs an admin-only GET/PUT /api/v1/realism/config surface.
The planner now exposes apply_payload(payload) / current_payload() /
reset_to_defaults() and reads its weights through mutable module
globals; pick() resolves the live values each call. Validation
catches negative weights, zero totals, out-of-range canary_probability,
unknown content_class names, and silently drops cross-list entries
(canary class on the user list, etc).
The orchestrator worker calls _refresh_realism_config(repo) on
startup and every 5 ticks (~5min at 60s interval). Operator changes
land within one refresh window with no bus signal — the simpler path
for a knob whose latency tolerance is minutes.
Adds GET /api/v1/realism/synthetic-files (paginated list, filters by
decky_uuid, persona, content_class) and
GET /api/v1/realism/synthetic-files/{uuid} (single row with last_body
and a truncated:bool flag set when the stored body is at the 64KB cap).
Repo gains count_synthetic_files() and get_synthetic_file(uuid). The
list view drops last_body to keep the wire payload bounded; the detail
endpoint is the only path that returns it. Read-only — orchestrator
remains the sole writer.
