Worktree setup and autoresearch Git prep silently misbehaved in pure Jujutsu workspaces (`.jj/repo/` present, no colocated `.git/`):
- `task/worktree.ts#getRepoRoot` threw a generic "Git repository not found for isolated task execution.", giving a jj user no hint about what was wrong.
- `autoresearch/git.ts#ensureAutoresearchBranch` returned a soft "Not in a git repository" warning, letting `/autoresearch` proceed with no branch isolation, baseline reset, or auto-commits.
Both paths now detect a pure jj workspace via a new `jj.isPureJjRepo` helper and surface an actionable Jujutsu-specific error pointing at `jj git init --colocate`. Colocated jj-git workspaces (both `.jj/` and `.git/` at the same root) and plain Git checkouts behave exactly as before.
Fixes#1935
- Added untracked worktree baseline capture via `untrackedPatch` and synthetic tree diffing.
- Added fallback-aware backend ordering by collecting host candidates and retrying alternates on unavailable PAL.
- Hardened overlay mount lifecycle by removing stale overlays and deleting upper/work dirs after unmount.
- Refined ZFS clone deletion to validate ownership and remove dataset+origin only when checks pass.
- Updated ProjFS integration to use extended-info callbacks and symlink metadata reads.
- Updated rcopy path handling to absolutize paths, and added `writeTree` plus combined shell timeout checks.
- Added unified isolation primitives (BackendKind, ProbeResult, IsoError) and resolve fallback selection logic.
- Added Diff, FileChange, and ChangeKind with default_diff choosing git mode or filesystem walk based on repository state.
- Added APFS/btrfs/zfs/reflink/overlayfs/projfs/rcopy/block-clone backends with platform-aware start, stop, and probe.
- Mapped backend operations to canonicalized paths, recursive clone helpers, rollback cleanup, and unavailable error mapping.
- Added unified native exports isoBackend/isoProbe/isoResolve/isoStart/isoStop/isoDiff and removed projfsOverlay APIs.
- Replaced task isolation resolver flow with ensureIsolation/cleanupIsolation and migrated mode handling to auto plus legacy-mode aliases.
- Fixed memory leak by cancelling idle compaction timer on event controller disposal.
- Fixed session resumption to preserve last non-empty session when starting fresh.
- Fixed stash detection to use git ref resolution instead of output parsing for reliability.
- Fixed secret obfuscation to deobfuscate restored session messages locally while keeping LLM messages obfuscated.
- Fixed stash pop operation to preserve staged changes with --index flag after task branch merges.
- Changed idle compaction settings from enum to numeric type for flexible configuration.
roboomp