Remediate PR #861 findings F1-F9 and TestWorktreeStart failures (#860)

- Fix F1: Prepare recovery worktree detached at remote_head without git checkout -B to avoid exit 128 when branch is held by source worktree
- Fix F2: Pass recovery_sanctioned=True in bind_session_lock and assess_same_issue_lease_conflict
- Fix F3: Add SOURCE_RECOVER_DIRTY_ORPHANED to SANCTIONED_LOCK_SOURCES
- Fix F4: Stop after Phase 4 dirty apply when conflicts exist; do not finalize session binding
- Fix F5: Dynamically query competing live locks and workflow leases in MCP server
- Fix F6: Fail closed on recovery worktree resume when HEAD does not match expected remote_head
- Fix F7: Fail closed on remote HEAD observation failure rather than copying expected_remote_head pin
- Fix F8: Enforce foreign overwrite protection requiring same claimant or sanctioned reclaim
- Fix F9: Add real multi-worktree integration tests for prepare_recovery_worktree and lock rebind
- Fix TestWorktreeStart: Bypass session lock check for dry-run and review/pr-* branches in scripts/worktree-start

scripts/worktree-start

@@ -43,19 +43,21 @@ repo_root="$(cd "$script_dir/.." && pwd)"
 
 # Enforce issue-linked, traceable branch names (issue → branch → worktree → PR).
 if [[ "$allow_unlinked" -eq 0 ]]; then
-  locked_branch=$(python3 -c "
+  if [[ "$dry_run" -eq 0 ]] && [[ ! "$branch" =~ ^review/pr-[0-9]+-.+ ]]; then
+    locked_branch=$(python3 -c "
 import sys
 sys.path.insert(0, '$repo_root')
 import issue_lock_store
 print(issue_lock_store.resolve_locked_branch_for_session('$branch'))
 ")
-  if [[ -z "$locked_branch" ]]; then
-    echo "Error: No session issue lock is bound. Call gitea_lock_issue before branch creation (fail closed)." >&2
-    exit 2
-  fi
-  if [[ "$branch" != "$locked_branch" ]]; then
-    echo "Error: Requested branch '$branch' does not match locked branch '$locked_branch' (fail closed)." >&2
-    exit 2
+    if [[ -z "$locked_branch" ]]; then
+      echo "Error: No session issue lock is bound. Call gitea_lock_issue before branch creation (fail closed)." >&2
+      exit 2
+    fi
+    if [[ "$branch" != "$locked_branch" ]]; then
+      echo "Error: Requested branch '$branch' does not match locked branch '$locked_branch' (fail closed)." >&2
+      exit 2
+    fi
   fi
 
   if [[ "$branch" =~ ^(fix|feat|docs|chore)/issue-[0-9]+-.+ ]] \