Documentation and fixture cleanup

[blms]

In this PR

• Added a couple of notes to the readme about Poetry 2+ and npm/tailwind
• Added documentation about loading fixtures, some RST cleanup
• Cleaned up all_data.json fixtures to resolve ContentType and other issues (see notes)

Notes

Fixture cleanup:

• I was getting errors about ContentTypes not existing, so I wrote and ran a quick python script to map ContentType.pk references to their names (natural key), as they are populated during migration but with mismatched PKs from the fixture.
• I also got some errors about Permission instances, so I removed those from the fixture file; they are also populated via migrations
• I was getting errors on LogEntry (and wagtail log entry) instances that referenced deleted models, so I just removed all of them from the fixture since they aren't needed for local dev
• At a certain point wagtail indices (indexentry and referenceindex) were causing errors, so I excluded them because they can be regenerated with management commands
• Finally, I just removed DB user sessions, since those are also not needed

Python script to clean fixtures

import json

with open("manuscript/fixtures/all_data.json") as all_data:
    data = json.load(all_data)

# map content_type_id --> natural key to prevent ContentType DoesNotExist on pk match
content_type_map = {}
for obj in data:
    if obj["model"] == "contenttypes.contenttype":
        pk = obj["pk"]
        fields = obj["fields"]
        content_type_map[pk] = [fields["app_label"], fields["model"]]

print(f"Found {len(content_type_map)} content types")

EXCLUDED_MODELS = [
    # wagtail indices
    "wagtailsearch.indexentry",
    "wagtailcore.referenceindex",
    # content types and permissions (populated by migrations)
    "contenttypes.contenttype",
    "auth.permission",
    # log entries (may refer to previously removed ContentTypes)
    "wagtailcore.modellogentry",
    "admin.logentry",
    # database user sessions
    "sessions.session",
]

fixtures = []
removed_fixtures = 0
remapped_contenttypes = 0
for obj in data:
    # remove fixtures for all excluded models from all_data
    if obj["model"] in EXCLUDED_MODELS:
        removed_fixtures += 1
        continue

    # remap content type to natural keys
    fields = obj.get("fields", {})
    if "content_type" in fields:
        ct_id = fields["content_type"]
        fields["content_type"] = content_type_map[ct_id]
        remapped_contenttypes += 1

    # add fixture
    fixtures.append(obj)

with open("manuscript/fixtures/all_data_portable.json", "w") as outfile:
    json.dump(fixtures, outfile, indent=4)

print(f"Removed {removed_fixtures} problematic fixtures")
print(f"Remapped {remapped_contenttypes} content_type_id references")