Prevent invalid projectId placement in Luna task creation

[FMnaga]

Problem

The Luna task-lane contract requires selecting a project but does not show that projectId belongs inside target. This leaves room for a top-level projectId, which the current create_thread schema rejects before task creation.

Changes

• Add one canonical Git-project create_thread argument example.
• State explicitly that top-level projectId is invalid.
• Parse that example in verify.sh and fail if target nesting, worktree routing, Luna/Max, or the packet placeholder drifts.

Verification

• RED: the new structural check failed with missing canonical create_thread project arguments before the contract update.
• GREEN: canonical argument structure check passed.
• sh -n plugins/sol-advisor/scripts/verify.sh passed in an LF checkout.
• Skill validation passed.
• Plugin validation passed.
• git diff --check origin/main..HEAD passed.

The full repository verify.sh currently stops on FAIL: manifest does not describe app-task routing; the same failure reproduces unchanged on upstream main at 154fd7a, before this patch.