chore(licence): normalise to MPL-2.0 + CC-BY-SA-4.0 (canonical pair) (#56)

Estate licence normalisation. LICENSES/={MPL-2.0,CC-BY-SA-4.0}; root
LICENSE=verbatim MPL-2.0 (GitHub display); code->MPL-2.0,
docs(.md/.adoc)->CC-BY-SA-4.0; vendored untouched. Residual mentions
(mostly legitimate anti-AGPL rules): 18. Manual-review licence PR.

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

.claude/CLAUDE.md

@@ -1,5 +1,5 @@
 <!--
-SPDX-License-Identifier: MPL-2.0
+SPDX-License-Identifier: CC-BY-SA-4.0
 Copyright (c) Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>
 -->
 ## Machine-Readable Artefacts

.github/FUNDING.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: MPL-2.0-or-later
+# SPDX-License-Identifier: MPL-2.0
 # Funding platforms for hyperpolymath projects
 # See: https://docs.github.com/en/repositories/managing-your-repositorys-settings-and-features/customizing-your-repository/displaying-a-sponsor-button-in-your-repository
 

.github/dependabot.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: MPL-2.0-or-later
+# SPDX-License-Identifier: MPL-2.0
 version: 2
 updates:
   - package-ecosystem: "cargo"

.github/workflows/aur-publish.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: MPL-2.0-or-later
+# SPDX-License-Identifier: MPL-2.0
 # Publish to Arch User Repository on release
 name: AUR Publish
 on:

.github/workflows/codeql.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: MPL-2.0-or-later
+# SPDX-License-Identifier: MPL-2.0
 # CodeQL security scanning for vext
 # Scans: GitHub Actions workflows (Rust not yet supported by CodeQL)
 

.github/workflows/container.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: MPL-2.0-or-later
+# SPDX-License-Identifier: MPL-2.0
 name: Container Build
 on:
   push:

.github/workflows/generator-generic-ossf-slsa3-publish.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: MPL-2.0-or-later
+# SPDX-License-Identifier: MPL-2.0
 # This workflow uses actions that are not certified by GitHub.
 # They are provided by a third-party and are governed by
 # separate terms of service, privacy policy, and support

.github/workflows/governance.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: PMPL-1.0-or-later
+# SPDX-License-Identifier: MPL-2.0
 name: Governance
 
 on:

.github/workflows/hypatia-scan.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: PMPL-1.0-or-later
+# SPDX-License-Identifier: MPL-2.0
 name: Hypatia Security Scan
 
 on:

.github/workflows/instant-sync.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: MPL-2.0-or-later
+# SPDX-License-Identifier: MPL-2.0
 # Instant Forge Sync - Triggers propagation to all forges on push/release
 name: Instant Sync
 on: