Add conversion gallery documentation for NWB to BIDS mapping

[Copilot]

Adds documentation section demonstrating fine-grained NWB file content extraction to BIDS sidecars per BEP32. Located after tutorials, uses same ecephys example data.

Changes

• docs/conversion_gallery.rst - New 450+ line documentation covering:

  • Reading NWB files with PyNWB (devices, electrode tables, ElectricalSeries)
  • BIDS sidecar generation (probes.tsv, electrodes.tsv, channels.tsv)
  • Field-to-field mapping tables for each metadata type
  • Subject/session metadata extraction to participants.tsv, sessions.tsv

• docs/index.rst - Added conversion_gallery to toctree after tutorials

• docs/conftest.py - Extended setup to pre-convert tutorial data for gallery examples

Example

Shows how NWB electrode table maps to BIDS sidecars:

# Read from NWB
electrodes_table = nwbfile.electrodes.to_dataframe()
# location, group_name, imp, filtering columns

# Extract to BIDS
bids_electrodes_df = pd.read_csv("sub-001_ses-A_electrodes.tsv", sep="\t")
# name, probe_name, location, impedance columns

Includes complete mapping tables like:

NWB Field	BIDS Field
electrodes.id	name
electrodes.group.device.name	probe_name
electrodes.imp	impedance (kOhms)

Screenshot

All code examples are executable and doc-tested (32 tests).

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Add conversion gallery</issue_title>
<issue_description>Showcasing the fine-grain file contents in line with BEP32</issue_description>

<agent_instructions>This should be a section of the docs after the tutorial that uses the same data but goes deep into the content of each NWB file (using PyNWB to read and display) and shows side-by-side what is extracted into BIDS sidecars</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Add conversion gallery #236

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
⚠️ Please upload report for BASE (conversion_gallery@84ce669). Learn more about missing BASE report.

Additional details and impacted files

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[CodyCBakerPhD]

@copilot Could you fix the pre-commit? Do you know why you didn't do it in the first place (given it is specified in the copilot instructions)

[CodyCBakerPhD]

@copilot Nevermind, I'll deal with it myself. This is a good start, thank you