feat: Auto-branch initiative system with per-project default branches
Planning tasks (research, discuss, plan, detail, refine) now run on
the project's defaultBranch instead of hardcoded 'main'. Execution
tasks (execute, verify, merge, review) auto-generate an initiative
branch (cw/<slug>) on first dispatch. Branch configuration removed
from initiative creation — it's now fully automatic.
- Add PLANNING_CATEGORIES/EXECUTION_CATEGORIES to branch-naming
- Dispatch manager splits logic by task category
- ProcessManager uses per-project defaultBranch fallback
- Phase dispatch uses project.defaultBranch for ensureBranch base
- Remove mergeTarget from createInitiative input
- Rename updateInitiativeMergeConfig → updateInitiativeConfig
- Add defaultBranch field to registerProject + UI
- Rename mergeTarget → branch across all frontend components
ca548c1eaa