diff --git a/.github/workflows/agent-dispatcher.yml b/.github/workflows/agent-dispatcher.yml
index 5b068860..46be77df 100644
--- a/.github/workflows/agent-dispatcher.yml
+++ b/.github/workflows/agent-dispatcher.yml
@@ -48,7 +48,7 @@ jobs:
 
     steps:
       - name: 📋 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: 🤖 Run Dispatcher Core
         shell: pwsh
diff --git a/.github/workflows/aggregate-telemetry.yml b/.github/workflows/aggregate-telemetry.yml
index 70735a20..fb8bdb09 100644
--- a/.github/workflows/aggregate-telemetry.yml
+++ b/.github/workflows/aggregate-telemetry.yml
@@ -31,7 +31,7 @@ jobs:
       report_created: ${{ steps.report.outputs.created }}
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Calculate target week
         id: week
diff --git a/.github/workflows/build-tools.yml b/.github/workflows/build-tools.yml
index 4cf52795..57c9a79c 100644
--- a/.github/workflows/build-tools.yml
+++ b/.github/workflows/build-tools.yml
@@ -51,7 +51,7 @@ jobs:
             ext: .exe
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Install Rust
         uses: dtolnay/rust-toolchain@stable
@@ -78,7 +78,7 @@ jobs:
       contents: write
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Download All Artifacts
         uses: actions/download-artifact@v4
diff --git a/.github/workflows/check-protocol-update.yml b/.github/workflows/check-protocol-update.yml
index ca6ed795..7db14ace 100644
--- a/.github/workflows/check-protocol-update.yml
+++ b/.github/workflows/check-protocol-update.yml
@@ -12,7 +12,7 @@ jobs:
   check-update:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       
       - name: Check for protocol updates
         id: check
diff --git a/.github/workflows/codex-review.yml b/.github/workflows/codex-review.yml
index d543e430..299a3c8e 100644
--- a/.github/workflows/codex-review.yml
+++ b/.github/workflows/codex-review.yml
@@ -105,7 +105,7 @@ jobs:
 
     steps:
       - name: 📥 Checkout PR
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           ref: refs/pull/${{ needs.should-run.outputs.pr_number }}/merge
           fetch-depth: 0
diff --git a/.github/workflows/commit-atomicity.yml b/.github/workflows/commit-atomicity.yml
index 6dec7e5c..3468396a 100644
--- a/.github/workflows/commit-atomicity.yml
+++ b/.github/workflows/commit-atomicity.yml
@@ -24,7 +24,7 @@ jobs:
 
     steps:
       - name: 📥 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
 
diff --git a/.github/workflows/copilot-auto-implementation.yml b/.github/workflows/copilot-auto-implementation.yml
index d569280b..b50773b9 100644
--- a/.github/workflows/copilot-auto-implementation.yml
+++ b/.github/workflows/copilot-auto-implementation.yml
@@ -93,7 +93,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Create Implementation Issue for Copilot
         id: create-issue
@@ -239,7 +239,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Check for E2E Test Configuration
         id: check-e2e
diff --git a/.github/workflows/copilot-meta-analysis.yml b/.github/workflows/copilot-meta-analysis.yml
index 66bda37e..9b50baa5 100644
--- a/.github/workflows/copilot-meta-analysis.yml
+++ b/.github/workflows/copilot-meta-analysis.yml
@@ -182,7 +182,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Download Analysis Data
         uses: actions/download-artifact@v6
diff --git a/.github/workflows/dependency-quarantine.yml b/.github/workflows/dependency-quarantine.yml
index 71c23f6c..58cf5d13 100644
--- a/.github/workflows/dependency-quarantine.yml
+++ b/.github/workflows/dependency-quarantine.yml
@@ -51,7 +51,7 @@ jobs:
 
     steps:
       - name: 📥 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           ref: ${{ github.event.pull_request.head.sha }}
 
@@ -205,7 +205,7 @@ jobs:
 
     steps:
       - name: 📥 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: 🎓 Graduate mature PRs
         run: |
@@ -275,7 +275,7 @@ jobs:
 
     steps:
       - name: 📥 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: 🔄 Trigger Context Research
         run: |
diff --git a/.github/workflows/dependency-sentinel.yml b/.github/workflows/dependency-sentinel.yml
index 328f1ed3..d3c838c3 100644
--- a/.github/workflows/dependency-sentinel.yml
+++ b/.github/workflows/dependency-sentinel.yml
@@ -67,7 +67,7 @@ jobs:
 
     steps:
       - name: 📥 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
 
@@ -195,7 +195,7 @@ jobs:
 
     steps:
       - name: 📥 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       # ─────────────────────────────────────────────────────────────
       # ACTION: New Dependabot PR - Ensure protocol is followed
@@ -416,7 +416,7 @@ jobs:
 
     steps:
       - name: 📥 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: 📊 Generate Weekly Report
         env:
diff --git a/.github/workflows/e2e-testing.yml b/.github/workflows/e2e-testing.yml
index 25c71e97..4df7fbd4 100644
--- a/.github/workflows/e2e-testing.yml
+++ b/.github/workflows/e2e-testing.yml
@@ -83,7 +83,7 @@ jobs:
     
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       
       - name: Detect E2E Framework
         id: detect
@@ -121,7 +121,7 @@ jobs:
     
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       
       - name: Setup Node.js
         uses: actions/setup-node@v4
@@ -213,7 +213,7 @@ jobs:
     
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           ref: ${{ github.head_ref || github.ref }}
       
diff --git a/.github/workflows/evolution-cycle.yml b/.github/workflows/evolution-cycle.yml
index 464f7673..a1d971d6 100644
--- a/.github/workflows/evolution-cycle.yml
+++ b/.github/workflows/evolution-cycle.yml
@@ -26,7 +26,7 @@ jobs:
     outputs:
       metrics_json: ${{ steps.metrics.outputs.json }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Calculate date range
         id: dates
diff --git a/.github/workflows/guardian-agent.yml b/.github/workflows/guardian-agent.yml
index 1e8cb3a2..9e388f25 100644
--- a/.github/workflows/guardian-agent.yml
+++ b/.github/workflows/guardian-agent.yml
@@ -37,7 +37,7 @@ jobs:
 
     steps:
       - name: 📋 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: 🔢 Resolve PR Number
         id: pr
diff --git a/.github/workflows/living-context.yml b/.github/workflows/living-context.yml
index 301eed1c..57b7c2c8 100644
--- a/.github/workflows/living-context.yml
+++ b/.github/workflows/living-context.yml
@@ -72,7 +72,7 @@ jobs:
 
     steps:
       - name: 📥 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
 
@@ -291,7 +291,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           ref: ${{ env.CONTEXT_PR_BRANCH }}
 
diff --git a/.github/workflows/planner-agent.yml b/.github/workflows/planner-agent.yml
index f184179a..659ba40c 100644
--- a/.github/workflows/planner-agent.yml
+++ b/.github/workflows/planner-agent.yml
@@ -47,7 +47,7 @@ jobs:
 
     steps:
       - name: 📋 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: 🗺️ Parse Roadmap from ARCHITECTURE.md
         id: roadmap
@@ -105,7 +105,7 @@ jobs:
 
     steps:
       - name: 📋 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: 🧠 Generate Issue Plan
         id: generate
diff --git a/.github/workflows/post-quarantine-analysis.yml b/.github/workflows/post-quarantine-analysis.yml
index bdbca796..ae71a90e 100644
--- a/.github/workflows/post-quarantine-analysis.yml
+++ b/.github/workflows/post-quarantine-analysis.yml
@@ -52,7 +52,7 @@ jobs:
     
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           ref: living-context/main
           fetch-depth: 0
@@ -113,7 +113,7 @@ jobs:
     
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       
       - name: Setup Node.js (for Gemini CLI)
         uses: actions/setup-node@v4
@@ -250,7 +250,7 @@ jobs:
     
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       
       - name: Download Analysis Report
         uses: actions/download-artifact@v6
diff --git a/.github/workflows/structure-validator.yml b/.github/workflows/structure-validator.yml
index 58df9959..61e540a3 100644
--- a/.github/workflows/structure-validator.yml
+++ b/.github/workflows/structure-validator.yml
@@ -23,7 +23,7 @@ jobs:
 
     steps:
       - name: 📥 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
 
@@ -86,7 +86,7 @@ jobs:
 
     steps:
       - name: 📥 Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
 
diff --git a/.github/workflows/sync-issues.yml b/.github/workflows/sync-issues.yml
index 60a6e4da..3db7f59c 100644
--- a/.github/workflows/sync-issues.yml
+++ b/.github/workflows/sync-issues.yml
@@ -47,7 +47,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
 
diff --git a/.github/workflows/update-protocol.yml b/.github/workflows/update-protocol.yml
index 03762dc5..f8ec5dba 100644
--- a/.github/workflows/update-protocol.yml
+++ b/.github/workflows/update-protocol.yml
@@ -28,7 +28,7 @@ jobs:
 
     steps:
       - name: 📥 Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
 
diff --git a/.github/workflows/workflow-validator.yml b/.github/workflows/workflow-validator.yml
index 33bb4693..7a89d2c3 100644
--- a/.github/workflows/workflow-validator.yml
+++ b/.github/workflows/workflow-validator.yml
@@ -68,7 +68,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Setup Rust
         uses: dtolnay/rust-toolchain@stable
@@ -113,7 +113,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Download Orchestrator (from artifact or pre-built)
         id: get-binary
@@ -227,7 +227,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Generate Markdown Report
         id: report