docs: full audit — fix 4 wrong port/research labels + consolidated research-track

A full audit of `doc/` plus root-level markdown files (27 files) against
the actual ground truth in the C++ code and the local Java repository at
`/Users/tarikmoussa/Desktop/conformallab/` revealed four pre-existing
mis-labels and a stale test count.  All are corrected here.

Audit findings — corrected
─────────────────────────

1. **`InversiveDistanceFunctional` mis-labelled as Java port** (4 doc sites)
   Empirical verification:
       find /Users/tarikmoussa/Desktop/conformallab -iname "*nversive*"
       (zero matches)
   The class does NOT exist in `de.varylab.discreteconformal`.  The C++
   implementation is built from Luo 2004 + Glickenstein 2011 + Bowers-
   Stephenson 2004 — new research, not a port.
   Fixed in: java-parity.md, references.md, add-inversive-distance.md.

2. **HyperIdeal Hessian mis-labelled as "Java has analytic Hessian"**
   Empirical verification: `HyperIdealFunctional.java:295-298`:
       public boolean hasHessian() { return false; }
   Java has NO Hessian at all.  Both the FD (Phase 4a) and the block-FD
   (Phase 9b) Hessians in C++ are research beyond the Java port.  The
   chain rule (b,a) → ℓ → ζ → α/β is the *mathematical formulation*
   from Springborn 2020, not something Java implements.
   Fixed in: java-parity.md.

3. **Stale test count** README:87 said "28 suites, 170 tests" — current
   actual is 35 suites, 176 CGAL + 36 non-CGAL.  Fixed.

4. **Tutorial framing** — `add-inversive-distance.md` was framed as
   "porting an InversiveDistanceFunctional.java" that does not exist.
   Rewritten as "Implementing the Inversive-Distance functional from
   Luo 2004" with prominent verification block at top.

New document: `doc/roadmap/research-track.md`
─────────────────────────────────────────────

Consolidates everything in conformallab++ that goes beyond a Java port:

* Items already on `main`: HyperIdeal FD Hessian, period matrix τ
  partial-research components, Möbius holonomy storage.
* Items on open PRs: CP-Euclidean (PR #8, port), Inversive-Distance
  (PR #8, research), block-FD Hessian (PR #9, research).
* Planned research with full citations:
  - **Phase 9b-analytic** — full analytic HyperIdeal Hessian via
    Schläfli identity (Schläfli 1858/60) and chain rule through
    ζ₁₃/ζ₁₄/ζ₁₅, citing Springborn 2020 §4, Cho-Kim 1999,
    Glickenstein 2011 §4.  Includes acceptance-criteria checklist
    (per-case derivative cross-checks, gauge null space, PSD,
    measured ≥ 3× speed-up, LaTeX correctness note).
  - **Phase 9a.2-analytic** — analytic inversive-distance Hessian
    via Glickenstein 2011 eq. (4.6).
  - **Phase 10c** — full uniformization for genus g ≥ 2 (Fuchsian
    group representation) — fully new research, no Java reference.
  - **geometry-central** GC-1/2/3 exploratory track.

* Java backlog summary: 11 worth-porting Java classes identified by
  the parallel survey (FundamentalPolygonUtility, DiscreteHarmonicForm-
  Utility, DiscreteHolomorphicFormUtility, CanonicalBasisUtility,
  HyperbolicCyclicFunctional, QuasiisothermicUtility, KoebePolyhedron, …).
  ~6 500 Java lines, ~5 months of porting work, organised by phase.

Updated documents
─────────────────

* CLAUDE.md
  - New "Port-vs-research maintenance rule" with empirical verification
    command and the four corrected mis-labels.
  - Doc map: 23 → 24 documents (research-track.md added).

* README.md
  - Test count corrected (170 → 176+36).

* doc/math/references.md
  - Luo 2004 entry corrected ("new research" instead of "not yet ported").
  - New entries for Bowers-Stephenson 2004, Glickenstein 2011,
    Bobenko-Pinkall-Springborn 2010, Schläfli 1858/60.

* doc/roadmap/phases.md
  - Phase 9 reorganised: 9a split into 9a.1 (port) / 9a.2 (research),
    9b clarified as research (Java has no Hessian), 9c expanded with
    Java line counts and effort estimates.
  - Phase 10 reorganised: 10a/10b/10c with their Java prerequisites
    explicitly listed; 10c flagged as "fully new research".
  - Phase 10b' added: parallel research track (hyperbolic functional,
    quasi-isothermic, Möbius centering).
  - Phase 10c' added: optional Java-port additions (Koebe, circle
    patterns, electrostatic sphere).

* doc/roadmap/java-parity.md
  - Inversive-distance row: ❌ Java, ❌ C++ (Phase 9a.2) — new research.
  - CP-Euclidean row added: ✅ Java, ❌ C++ (Phase 9a.1) — port.
  - HyperIdeal Hessian row: ❌ Java, ⚠️ FD + block-FD in C++.
  - Worth-porting table replaced with the survey results (12 classes,
    Java line counts, suggested phases).
  - "HyperIdeal Hessian: FD vs analytic" section rewritten with the
    correction notice.

* doc/tutorials/add-inversive-distance.md
  - Rewritten end-to-end with prominent verification block at top.
  - Now correctly framed as "Implementing the Inversive-Distance
    functional from Luo 2004" — research, not port.
  - Includes the four required cross-validations:
    limit cases, Bowers-Stephenson round-trip, FD-vs-analytic,
    cross-validation against euclidean_functional at u=0.
  - New "How to know if it's a port or research" closing section
    with the empirical verification command.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

CLAUDE.md

@@ -288,9 +288,34 @@ Root-level files added at v0.7.0:
 - `scripts/try_it.sh` — one-script quickstart: build → 209 tests → example run
 - CMake install target: `cmake --install build --prefix /usr/local` → headers land in `include/conformallab/`
 
+## Port-vs-research maintenance rule (2026-05-21 audit)
+
+Before claiming something "ports X from Java", **verify empirically**:
+
+```bash
+find /Users/tarikmoussa/Desktop/conformallab -iname "*X*"
+grep -r "ClassName" /Users/tarikmoussa/Desktop/conformallab/src
+```
+
+If zero matches, the work is **new research** — add it to
+`doc/roadmap/research-track.md` with primary literature citations,
+**not** to `doc/roadmap/java-parity.md`.
+
+The 2026-05-21 audit found four pre-existing mis-labels:
+
+| Item | Wrong claim | Reality |
+|---|---|---|
+| `InversiveDistanceFunctional` | "Java port (Luo 2004)" | No such Java class exists |
+| HyperIdeal Hessian (FD) | "Phase 4a" | Research — Java has `hasHessian()==false` |
+| HyperIdeal Hessian (analytic) | "Phase 9b port" | Research — derivation via Schläfli 1858 |
+| Tutorial framing | "ports `InversiveDistanceFunctional.java`" | Implementation from Luo 2004 + Glickenstein 2011 |
+
+All four are corrected as of this commit.  Future contributors must
+follow the empirical verification rule above before any new claim.
+
 ## Documentation map
 
-23 documents across 6 categories. Read the relevant one before reasoning from scratch
+24 documents across 6 categories. Read the relevant one before reasoning from scratch
 — do not hallucinate content that is already written down.
 
 ### Mathematics & theory
@@ -338,6 +363,7 @@ Root-level files added at v0.7.0:
 |---|---|
 | Phases 1–10 with status and sub-tasks | `doc/roadmap/phases.md` |
 | Which Java classes are ported, which are planned, which are skipped? | `doc/roadmap/java-parity.md` |
+| New research items (beyond Java) — citations, acceptance criteria | `doc/roadmap/research-track.md` |
 
 ### Tutorials & onboarding