chore(licence): normalise to MPL-2.0 (code) + CC-BY-SA-4.0 (docs) (#25)

- LICENSES/ = {MPL-2.0.txt, CC-BY-SA-4.0.txt}; root LICENSE = verbatim MPL-2.0 (GitHub display)
- SPDX: code -> MPL-2.0, docs (.md/.adoc) -> CC-BY-SA-4.0; metadata/badge fixes; vendored untouched

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

Author: hyperpolymath

.github/workflows/codeql.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: PMPL-1.0
+# SPDX-License-Identifier: MPL-2.0
 name: CodeQL Security Analysis
 
 on:

.github/workflows/scorecard.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: PMPL-1.0
+# SPDX-License-Identifier: MPL-2.0
 name: Scorecards supply-chain security
 
 on:

.github/workflows/secret-scanner.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: PMPL-1.0
+# SPDX-License-Identifier: MPL-2.0
 name: Secret Scanner
 
 on:

.machine_readable/agent_instructions/README.adoc

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: MPL-2.0
+// SPDX-License-Identifier: CC-BY-SA-4.0
 // Copyright (c) 2026 Jonathan D.A. Jewell (hyperpolymath) <j.d.a.jewell@open.ac.uk>
 = Agent Instructions
 :toc: preamble

.machine_readable/svc/k9/README.adoc

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: MPL-2.0
+// SPDX-License-Identifier: CC-BY-SA-4.0
 = K9 Contractiles
 :toc: left
 :icons: font

ABI-FFI-README.md

@@ -1,4 +1,4 @@
-<!-- SPDX-License-Identifier: MPL-2.0 -->
+<!-- SPDX-License-Identifier: CC-BY-SA-4.0 -->
 # Universal Extension Format (UXF) ABI/FFI Documentation
 
 ## Overview

CHANGELOG.md

@@ -1,5 +1,5 @@
 <!--
-SPDX-License-Identifier: MPL-2.0
+SPDX-License-Identifier: CC-BY-SA-4.0
 SPDX-FileCopyrightText: 2026 Jonathan D.A. Jewell (hyperpolymath)
 -->
 

CODE_OF_CONDUCT.md

@@ -1,4 +1,4 @@
-<!-- SPDX-License-Identifier: MPL-2.0 -->
+<!-- SPDX-License-Identifier: CC-BY-SA-4.0 -->
 # Code of Conduct
 
 ## Our Pledge

CONTRIBUTING.md

@@ -1,6 +1,6 @@
 # Contributing to Universal Extension Format (UXF)
 
-<!-- SPDX-License-Identifier: MPL-2.0 -->
+<!-- SPDX-License-Identifier: CC-BY-SA-4.0 -->
 
 Thank you for your interest in contributing to Universal Extension Format!
 

EXPLAINME.adoc

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: MPL-2.0
+// SPDX-License-Identifier: CC-BY-SA-4.0
 = Universal Extension Format (UXF) — Show Me The Receipts
 :toc:
 :icons: font