docs: the board regression document names a developer home path and the scan check is red #11083

Part of the night-loop epic #11063. Self-critique: PR #11082 (the board regression document) merged with its scan check red: the guard "Block hardcoded developer home paths" reports FAIL new docs/analog/board-regression-2026-10-19.md (1 occurrence). The check is not required, so auto-merge did not wait for it, and my landing script did not look for the path. The merged document names the developer's home directory in its toolchain line.

Goal

The board regression document names no developer home path, the scan check is green for it, and the landing procedure refuses such a path before a push.

Requirements

• FR-001: docs/analog/board-regression-2026-10-19.md MUST replace the absolute developer home path in its toolchain line with a repository-relative or variable form (for example $(git rev-parse --git-common-dir)/../build/fpga/openxc7), and MUST keep every other number and command unchanged.
• FR-002: The landing procedure of the night loop MUST refuse a staged file that contains a developer home path before it pushes; the rule belongs to the decisions of tri land (specs/tri/land/land.t27), and until that spec carries it the throwaway landing script MUST check it.
• FR-003: The lesson MUST be recorded in the night-loop memory and in the Traps of the analog skill: lane documents are written without absolute home paths.

Scenarios

• Given the fixed document, when the scan check runs, then it reports no new occurrence for that file.
• Given a staged file with a developer home path, when the landing procedure runs, then it refuses and names the file and line.

Boundary

• docs/analog/board-regression-2026-10-19.md

Success Criteria

• git grep -n "/Users/" docs/analog/board-regression-2026-10-19.md exits non-zero.
• python3 tools/check_devhome_paths.py exits 0 or reports no new entry for that file.
• git diff --stat shows 1 file changed and 1 line replaced.