URTD: Dynamics of the Uncertainty Boundary

Summary of changes from v2.1

This update completes the mathematical closure target identified in the v2.1 conclusion.

Appendix A added: Symplectic Invariance of the Minimal Recursion Action Cell. The appendix establishes that Amin⁡A_{\min} Amin is invariant under admissibility-preserving canonical transformations, using only existing URT operators. The argument proceeds in four steps: physical scalars are coordinate-independent by construction; a completed recursion event produces a residual structure Rn={In,σn}R_n = \{I_n, \sigma_n\} Rn={In,σn} inherited by the subsequent event; non-canonical transformations alter this residual and therefore constitute physical changes to the recursion sequence rather than coordinate relabelings; canonicality is therefore required for admissibility preservation across the sequence. No new operators are introduced.

Section 6.4 updated: One sentence added directing the reader to Appendix A at the point where the minimal symplectic area is introduced.

Section 7 (Conclusion) updated: A sixth point added acknowledging that coordinate independence of the minimal recursion action cell is now established. The open items list updated to reflect that symplectic invariance is closed; the remaining open tasks are the conjugate-mapping uniqueness question, the localization convention derivation, and process-class universality of Amin⁡A_{\min} Amin.

Abstract updated: Final sentence revised to reflect that the coordinate independence result is established rather than remaining open.

No content changes were made to Sections 1 through 6.3, 6.5 through 6.10, or the References. All empirical values, operator definitions, and scope statements are unchanged.