chore(deps): bump GitHub Actions to latest versions

- actions/upload-artifact: v4 → v7
- actions/setup-python: v5 → v6
- actions/setup-node: v4 → v6 (docs-deploy)
- pnpm/action-setup: v4 → v6 (docs-deploy)
- actions/deploy-pages: v4 → v5

Closes #10, #11, #12, #13, #14

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

Author: sirdeggen

.github/workflows/ci.yml

@@ -66,7 +66,7 @@ jobs:
 
       - name: Upload conformance reports
         if: always()
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           name: conformance-report
           path: conformance/reports/
@@ -76,7 +76,7 @@ jobs:
       # See conformance/GO_PLAN.md for migration status.
       - name: Publish conformance vectors
         if: github.ref == 'refs/heads/main'
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           name: conformance-vectors
           path: conformance/vectors/

.github/workflows/codegen.yml

@@ -67,7 +67,7 @@ jobs:
             -o conformance/generated/messaging/types.gen.d.ts
 
       # ── Python types (datamodel-code-generator / pydantic v2) ────────────
-      - uses: actions/setup-python@v5
+      - uses: actions/setup-python@v6
         with:
           python-version: '3.12'
       - name: Install datamodel-code-generator

.github/workflows/conformance.yml

@@ -28,7 +28,7 @@ jobs:
         working-directory: ${{ github.workspace }}/conformance/runner/ts
       - name: Upload TS conformance reports
         if: always()
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           name: ts-conformance-reports
           path: conformance/reports/
@@ -38,7 +38,7 @@ jobs:
       # See conformance/GO_PLAN.md for migration status.
       - name: Publish conformance vectors
         if: github.ref == 'refs/heads/main'
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           name: conformance-vectors
           path: conformance/vectors/

.github/workflows/docs-deploy.yml

@@ -28,9 +28,9 @@ jobs:
         with:
           fetch-depth: 0
 
-      - uses: pnpm/action-setup@v4
+      - uses: pnpm/action-setup@v6
 
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@v6
         with:
           node-version: '24'
           cache: 'pnpm'
@@ -66,4 +66,4 @@ jobs:
       url: ${{ steps.deployment.outputs.page_url }}
     steps:
       - id: deployment
-        uses: actions/deploy-pages@v4
+        uses: actions/deploy-pages@v5