Fix missing refdes and thick strokes in custom symbols

[seveibar]

Summary

• Add a {NAME} schematic text element to generated custom symbols unless the source already contains a reference placeholder.
• Preserve EasyEDA RECT lineWidth after converting it to schematic units.
• Add real JLCPCB reproduction fixtures for C354900 and C1527439 with circuit JSON and visual assertions.

Reproduction

The JLCPCB imports for fuse C354900 and MOV C1527439 emit custom symbol elements. Custom symbols do not receive the automatic chip-box designator, so their names were absent. Their EasyEDA rectangle line width was also omitted, causing tscircuit to use its 0.12 default instead of the imported 1 x 0.02 = 0.02 width.

The regression test renders both parts with realistic F1 and RV1 names and verifies the resolved schematic text and 0.02 rectangle stroke. Existing custom-symbol snapshots are refreshed to document the general behavior.

Verification

• bun test: 188 pass, 0 fail, 63 snapshots
• bun run build
• bun run format:check
• git diff --check