Resolve all 374 ruff errors across 36 Python files (E501, E702, E722,
E741, F821, F841, invalid-syntax) bringing `ruff check .` to zero
errors repo-wide with line-length=100.
Rewrite CI workflow to use uv for dependency management, whole-repo
`ruff check .`, py_compile syntax gate, and merged python-tests job.
Add pyproject.toml with ruff config and uv dependency groups.
CI structure proposed by hcm444.
Bit-accurate Python model (fpga_model.py) mirrors full DDC RTL chain:
NCO -> mixer -> CIC -> FIR with exact fixed-point arithmetic matching
RTL DSP48E1 pipeline behavior including CREG=1 delay on CIC int_0.
Synthetic radar scene generator (radar_scene.py) produces ADC test
vectors for 5 scenarios: DC, single target (500m), multi-target (5),
noise-only, and 1 MHz sine wave.
DDC co-sim testbench (tb_ddc_cosim.v) feeds hex vectors through RTL
DDC and exports baseband I/Q to CSV. All 5 scenarios compile and run
with Icarus Verilog (iverilog -g2001 -DSIMULATION).
Comparison framework (compare.py) validates Python vs RTL using
statistical metrics (RMS ratio, DC offset, peak ratio) rather than
exact sample match due to RTL LFSR phase dithering. Results: 5/5 PASS.
Jason