Operators wanted new agent sandboxes and review-bot monitoring to stay on the configured base (or dev) instead of drifting to whichever branch is currently checked out. This updates runtime + template scripts and adds coverage for base-selection behavior.

Constraint: Preserve explicit --base overrides and existing branch metadata handling

Rejected: Always hardcode main | repos in this toolchain default to dev and may configure multiagent.baseBranch

Confidence: high

Scope-risk: moderate

Reversibility: clean

Directive: Keep runtime scripts and templates in lockstep for branch-base resolution

Tested: bash -n scripts/agent-branch-start.sh scripts/review-bot-watch.sh templates/scripts/agent-branch-start.sh templates/scripts/review-bot-watch.sh

Tested: node --test --test-name-pattern 'review-bot-watch script prints help after setup' test/install.test.js

Tested: node --test --test-name-pattern 'setup agent-branch-start defaults base to configured/dev and keeps current checkout branch unchanged' test/install.test.js

Not-tested: node --test --test-name-pattern 'codex-agent defaults to configured/dev base and keeps current checkout branch unchanged' test/install.test.js (timed out)