v0.4.0

Added

• NAM import level normalisation, like NAM plugins: nam::convert::normalise_level scales G2 (after the pedal's
  saturation, so a pure volume change) so that every model plays at the same level, NORMALISED_LEVEL_DB,
  measured with pedal_level_db on pink noise and calibrated on the pedal to its built-in bass amps (two SVT-VR
  models 6 dB apart raw land within 0.2 dB of each other; un-normalised they sat 13–19 dB below the built-in amps). Models span about 17 dB raw; the conversions inherit
  the official app's level, which plays models quietly (24–34 dB below their own output). On by default for
  Device::import_nam_file; Device::import_nam_file_as(.., normalise), Python nam.convert(..., normalise=True)
  and Device.import_nam_file(..., normalise=...). nam::Model::loudness (the file's metadata). Example
  nam_level.
• ir module: read and write WAV files (Wav: PCM 8–32-bit and float, any channel count), and convert, the
  official app's IR conversion recovered from its native code: files that aren't 48 kHz mono 24-bit are converted
  first (first channel, JUCE's resampler, resample_like_app, 24-bit), then the first 2048 samples are reversed and
  scaled so the 398 Hz – 3 kHz response is centred on 0 dB (app_gain). Identical to eleven captured imports
  (tests/ir_import.rs). Device::import_ir_file(slot, path) converts and uploads, named like the app (first 16
  characters). Also a windowed-sinc resample. Python: open_stomp.ir, Device.import_ir_file. Examples
  ir_check, ir_test_files (designed test IRs, tests/data/ir) and ir_capture_check.
• The pedal plays only the first 384 taps of an uploaded IR (re-amped probe IRs; ir::PEDAL_IR_TAPS, docs/05).
• ir::convert_optimised / Method::Optimised (feature nam): a 384-tap minimum-phase filter fitted to the whole
  IR's 1/6-octave response, at the level the app means to give it. On fifteen bass IRs in software, what the pedal
  plays is 2.4 dB rms from the full IR against 7.9 dB for the official conversion, which leaves IRs with a delayed
  start 35–44 dB too quiet. Confirmed on hardware (re-amped: 2.1 vs 4.8 dB rms, and 5.5 dB vs 16 dB rms plus 46 dB
  too quiet for a delayed IR). The default for Device::import_ir_file (Python too); convert_with,
  Device::import_ir_file_with(.., Method::App) for the official conversion, Python method=, example ir_compare.

Fixed

• User IR uploads put the slot in data-header byte 0, as the official app does (it was in byte 1, NAM's slot byte,
  so only slot 0 was right). upload::Chunk::ir_slot; Reassembler reports either slot.