Add a kicad_export checkbox to parameters, allowing users to control
which specifications appear as fields in the KiCad HTTP library API.
Parameters with kicad_export enabled are included using their formatted
value, without overwriting hardcoded fields like description or Stock.
- Use empty Response instead of JsonResponse(null) for 304 Not Modified
to avoid sending "null" as response body
- Guard parse_url() result with is_string() since it can return false
for malformed URLs
- Move storage location tracking inside the availability check so
expired and unknown-quantity lots don't contribute locations
- Add comprehensive KiCadHelperTest with 14 test cases covering:
- Stock quantity calculation (zero, single lot, multiple lots)
- Stock exclusion of expired and unknown-quantity lots
- Storage location display (present, absent, multiple)
- Datasheet URL resolution by type name, attachment name, PDF extension
- Datasheet fallback to Part-DB URL when no match
- "Data sheet" (with space) name variant matching
- Fix PDF extension detection for external attachments (getExtension()
returns null for external-only attachments, now also parses URL path)
- Add Stock field showing total available quantity across all part lots
- Add Storage Location field when parts have stored locations
- Resolve actual datasheet PDF from attachments (by type name, attachment
name, or first PDF) instead of always linking to Part-DB page
- Keep Part-DB page URL as separate "Part-DB URL" field
- Add ETag and Cache-Control headers to all KiCad API endpoints
- Support conditional requests (If-None-Match) returning 304
- Categories/part lists cached 5 min, part details cached 1 min
* Add supplier information to KiCad part exports
- Include supplier name and part numbers from order details in KiCad exports
- Handle multiple suppliers with sequential numbering (Supplier 2, Supplier 3, etc.)
- Include both active and obsolete order details for comprehensive supplier info
- Add null checks to prevent errors when supplier or part number is missing
* Add SPN suffix to field name
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Co-authored-by: Jan Böhmer <mail@jan-boehmer.de>
