pr-merge-baselisted

# Smart Merge to Base Branch Merge one or more PRs into the base branch (main/master) using queue-like sequencing. ## Process 1. **Detect base branch**: Identify the default branch (`main`, `master`, or repo-specific) via `git remote show origin` or repo conventions. 2. **Enumerate PRs**: List all PRs to merge. For each, fetch the latest HEAD. 3. **Create checkpoint**: Record the current base branch tip as a rollback point. ``` CHECKPOINT=$(git rev-parse HEAD) ``` 4. **Create integration branch**: Work on a temporary branch to validate before touching base. ``` git checkout -b merge-queue/<timestamp> <base> ``` 5. **Determine merge order**: - If the user specifies an order, use that. - Otherwise, compute dependency/topological order (if PR B depends on PR A, merge A first). - If PRs are independent with no clear ordering, present the list and ask the user to confirm or reorder before proceeding. 6. **Sequential merge with conflict handling** — for each PR in order: a. Attempt `git merge --no-ff <pr-branch>` into the integration branch. b. If merge succeeds cleanly, continue to next PR. c. If conflicts occur: - Analyze each conflict file using `difft` and codebase context. - Apply resolution using structural understanding (prefer base for formatting, PR for logic). - If a conflict cannot be resolved with confidence, **abort this merge** (`git merge --abort`), **stop and report** the conflict to the user with both si