v0.44.3: ONT amplicon uses dedicated config section

What's Changed

Bug Fix

• ONT amplicon pipeline was using PacBio Sequel model -- the pipeline read model_file from pacbio_params (default: ERRHMM-SEQUEL.model) instead of an ONT-specific config section. ONT reads were simulated with PacBio error profiles. (#79)

Fix

• Added ont_amplicon_params config section with ERRHMM-ONT.model as default
• ONT pipeline reads from ont_amplicon_params (not pacbio_params)
• CLI routes --model-file to ont_amplicon_params for --platform ont
• Null-safe parameter handling (explicit null values fall back to defaults)
• OntAmpliconConfig TypedDict, schema validation, path resolution

Configuration

"ont_amplicon_params": {
    "model_type": "errhmm",
    "model_file": "reference/pbsim3/ERRHMM-ONT.model",
    "threads": 8,
    "accuracy_mean": 0.95
}

Documentation

• ONT configuration section in amplicon simulation guide
• ont_amplicon_params section in configuration reference
• Changelog updated

Full Changelog: v0.44.2...v0.44.3