docs: citation audit + correct 8 mis-citations; add Phases 12/13

External reviewer pass over the literature references. Verified entries
against arXiv/DOI/publisher and corrected misattributions that had
propagated across the docs.

Corrected citations (consistent across all docs):
- Bowers-Bowers-Lutz 2026: title was the 2017 paper's
  -> "Rigidity of Koebe Polyhedra and Inversive Distance Circle Packings"
- Liouville theorem: "Springborn 2019" -> Pinkall & Springborn,
  Geom. Dedicata 214 (2021)
- Bobenko-Pinkall-Springborn: "G&T 14 (2010)" -> G&T 19(4) (2015), 2155-2215
- Optimal Cone Singularities: "Crane, Soliman, Ben-Chen, Schroeder"
  -> Soliman, Slepcev, Crane, ACM TOG 37(4)
- Schlaefli formula: "Rivin, Springborn 1999" -> Rivin, Schlenker
- Quasiconformal distortion: "Springborn, Veselov" -> Born, Buecking,
  Springborn (arXiv:1505.01341)
- Period matrices: "Bobenko, Buecking 2009" (was Bobenko-Mercat-Schmies'
  title) -> Bobenko-Mercat-Schmies 2011 + genuine Bobenko-Buecking 2021
- Fabricated entry: "Alexa 2020, DOI 10.1145/3414685.3417840" pointed to
  an unrelated paper (Pixelor) -> Bunge, Herholz, Kazhdan, Botsch 2020
- Stripe Patterns: "Bonneel et al. 2015" -> Knoeppel, Crane, Pinkall,
  Schroeder 2015

Equation-number corrections (verified against the PDFs):
- Glickenstein 2011 "eq. 4.6" -> "§5.2" (no such equation label exists)
- Springborn 2020 "eq. 4.6" -> "§4 variational gradient"
- inversive-distance attribution softened to classical inversive distance

Other:
- DBFEnergy bibliography (separate repo) and convergence half-sentence in
  novelty-statement.md §3.3 (Bobenko-Buecking 2021)
- Status legend (implemented vs planned) at top of references.md
- New Phase 12 (decorated DCE & geometric transition, Chain A, near-term)
  and Phase 13 (canonical tessellations & polyhedral realisation, Chain B
  capstone) in phases.md + research-track.md; 10c scope-boundary note
  clarifying infrastructure vs Lutz-specific algorithms

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

doc/reviewer/questions.md

@@ -35,7 +35,7 @@ phases whose existence is settled but whose priority is open:
 | **9f** | RESEARCH | Discrete Laplace–Beltrami on **non-triangular** polygonal meshes (virtual-node / generalised cotangent), making DCE work on quad / Voronoi tessellations without re-triangulation | Polygon Laplacians (2011 *SIGGRAPH* + 2020 *TOG*) |
 | **10c + 10c′** | planned | Canonical Delaunay tessellations of decorated hyperbolic surfaces; Koebe polyhedron realisation (KAT) with rigidity-aware Newton | Canonical tessellations of decorated hyperbolic surfaces (2023, *Geom. Dedicata*); rigidity of circle / hyperideal polyhedra (2026, preprint) |
 | **10e** | planned | Quasi-isothermic maps (~800 lines Lawson-correspondence) — generalises conformality to meshes where exact conformality is impossible.  Six new classes including a discrete Beltrami-field solver. | Java original `QuasiisothermicUtility` line; no obvious single-paper reference in the existing literature index |
-| **10b** | planned | Hyperelliptic surfaces (genus g ≥ 2 with Z₂ symmetry); period matrices with block-diagonal structure; Penner-coordinate variant via `HyperIdealHyperellipticUtility` | Bobenko–Bücking 2009 *Conformal Structures and Period Matrices of Polyhedral Surfaces* |
+| **10b** | planned | Hyperelliptic surfaces (genus g ≥ 2 with Z₂ symmetry); period matrices with block-diagonal structure; Penner-coordinate variant via `HyperIdealHyperellipticUtility` | Bobenko–Mercat–Schmies 2011 *Period Matrices of Polyhedral Surfaces* / Bobenko–Bücking 2021 *Convergence of discrete period matrices* |
 | **9d.4** | planned | Möbius centring of Poincaré-disk layouts as a *variational* problem (Lorentz energy with full gradient + Hessian), replacing today's iterative Fréchet-mean fallback in `normalise_hyperbolic()` | Java original `MobiusCenteringFunctional`; closest published context: decorated-DCE Möbius normalisation, also used in canonical-tessellation post-processing |
 
 **Question A:** which of these (if any) would unblock concrete
@@ -104,7 +104,7 @@ We have:
   [`doc/math/hyperideal-hessian-derivation.md`](../math/hyperideal-hessian-derivation.md)
   (805 lines, all sign pitfalls covered, references Schläfli 1858,
   Milnor 1982, Vinberg 1993, Cho–Kim 1999, Glickenstein 2011,
-  Springborn 2020, Rivin–Springborn 1999).
+  Springborn 2020, Rivin–Schlenker 1999).
 
 **Question:**