Let local-dev.sh deploy from a sibling git worktree

[Yicong-Huang]

Feature Summary

bin/local-dev.sh always builds and runs the stack from its own checkout, so deploying a PR branch means either switching the main checkout's branch (disrupting in-flight work) or copying the tooling into each worktree. There is no way to keep one stable copy of the orchestration script while pointing the build/run at a different worktree.

Proposed Solution or Design

Separate the orchestration tree (where local-dev.sh, tui.py, and the docker overlay live — always used from the canonical checkout) from the application source tree that gets built and run.

• up / auto accept --worktree=PATH or --branch=NAME (resolved to the worktree that has it checked out) to deploy a sibling worktree; a plain up returns to the current checkout.
• The selection persists to $STATE_DIR/deploy-source, so status / down / logs / single-service rebuild / auto all follow the active deployment, and status --json reports worktree / source.
• Build stamps are namespaced per source tree so switching worktrees never skips a required rebuild.
• The interactive TUI mirrors the CLI: u / a accept the selectors and re-point the banner to the active tree.

Invalid --branch / --worktree fail fast with a clear message.

Affected Area

Deployment / Infrastructure