On NixOS (and other non-FHS systems) /bin/bash does not exist, so
scripts with an absolute shebang fail to run. Switch the remaining
holdouts to /usr/bin/env bash: eleven scripts/*.sh,
test-infrastructure/run.sh, and the three Claude Code hook scripts
emitted by src/cli/cli.c (gate, session reminder, subagent reminder).
Distilled from PR #674, with parser-test coverage preserved: the
infra_parse_shell* fixtures in tests/test_pipeline.c intentionally keep
#!/bin/bash so absolute-path shebang extraction stays covered, and
tests/repro fixtures are untouched.
Also replace the GitHub-PAT-shaped fixture string flagged in the #674
thread with an obviously fake placeholder (ghp_FAKE...) that still
matches the ghp_ + 36-alnum secret detector.
Co-authored-by: Sandro Jäckel <sandro.jaeckel@gmail.com>
Signed-off-by: Martin Vogel <martin.vogel.tech@gmail.com>