Add /set_bandwidth and /set_fir_taps HTTP endpoints to api.rs.
Add applyCapabilities(caps) function to app.js that shows/hides:
- PTT button and TX meters: capabilities.tx
- TX limit row: capabilities.tx_limit
- VFO row: capabilities.vfo_switch
- Signal meter row: capabilities.signal_meter
- Filters panel: capabilities.filter_controls
Called from render() whenever capabilities are present; runs on both
initial /status response and every SSE event.
Add a Filters panel to index.html with bandwidth slider (1..500 kHz)
and FIR taps select (16/32/64/128/256); hidden by default, revealed by
applyCapabilities when filter_controls is set. Each control dispatches
to the corresponding HTTP endpoint on change.
Sync filter state from update.filter in render() to keep slider/select
in sync with server-side DSP state.
Fix missing struct fields in test helpers across remote_client.rs,
trx-frontend-http-json/server.rs, trx-frontend-rigctl/server.rs, and
trx-core controller tests (handlers.rs, machine.rs).
Update aidocs/UI-CAPS.md: all tasks UC-01..UC-09 marked [x].
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Signed-off-by: Stan Grams <sjg@haxx.space>
sjg