kicad-cli's `pcb export svg` defaults to `--page-size-mode 0` (the full drawing sheet), so only the area inside the sheet is plotted -- board geometry past the page edge is left out. Pass `--exclude-drawing-sheet` and `--page-size-mode 2` (board area only) so the output is sized to the board's bounding box and the full board is rendered. Both flags exist since KiCad 7, so KiCad 8/9 are unaffected.
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