chore: fix license headers to PMPL-1.0-or-later

- Update SPDX identifiers from AGPL to PMPL
- Ensure LICENSE file uses PMPL-1.0-or-later
- Maintain consistency with palimpsest-license repo

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: Your Name

.github/workflows/codeql.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: AGPL-3.0-or-later
+# SPDX-License-Identifier: PMPL-1.0-or-later
 name: CodeQL Security Analysis
 
 on:

.github/workflows/quality.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: AGPL-3.0-or-later
+# SPDX-License-Identifier: PMPL-1.0-or-later
 name: Code Quality
 on: [push, pull_request]
 

.github/workflows/scorecard.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: AGPL-3.0-or-later
+# SPDX-License-Identifier: PMPL-1.0-or-later
 name: OSSF Scorecard
 on:
   push:

.github/workflows/security-policy.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: AGPL-3.0-or-later
+# SPDX-License-Identifier: PMPL-1.0-or-later
 name: Security Policy
 on: [push, pull_request]
 

.github/workflows/wellknown-enforcement.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: AGPL-3.0-or-later
+# SPDX-License-Identifier: PMPL-1.0-or-later
 name: Well-Known Standards (RFC 9116 + RSR)
 on:
   push:

.github/workflows/workflow-linter.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: AGPL-3.0-or-later
+# SPDX-License-Identifier: PMPL-1.0-or-later
 # workflow-linter.yml - Validates GitHub workflows against RSR security standards
 # This workflow can be copied to other repos for consistent enforcement
 name: Workflow Security Linter

LICENSE

@@ -1,4 +1,4 @@
-SPDX-License-Identifier: PMPL-1.0
+SPDX-License-Identifier: PMPL-1.0-or-later
 SPDX-FileCopyrightText: 2024-2025 Palimpsest Stewardship Council
 
 ================================================================================