Add GitHub Pages SPA fallback

Author: liangping

.github/workflows/deploy.yaml

@@ -51,6 +51,9 @@ jobs:
       - name: Copy logos
         run: cp -rf logos explorer/dist/
 
+      - name: Create SPA 404 fallback
+        run: cp explorer/dist/index.html explorer/dist/404.html
+
       - name: Upload Pages artifact
         uses: actions/upload-pages-artifact@v3
         with:

.github/workflows/pr-review.yaml

@@ -54,3 +54,6 @@ jobs:
         run: yarn build
         env:
           NODE_OPTIONS: --max_old_space_size=4096
+
+      - name: Verify SPA 404 fallback
+        run: cp explorer/dist/index.html explorer/dist/404.html && test -s explorer/dist/404.html

docs/github-automation.md

@@ -12,6 +12,8 @@ In repository settings:
 
 The `Deploy to GitHub Pages` workflow builds the `explorer` submodule, copies this repository's chain configs and logos into the build output, uploads `explorer/dist`, and deploys it through GitHub Pages.
 
+The workflow also copies `index.html` to `404.html`. GitHub Pages serves `404.html` for missing paths, so direct visits to Vue Router history-mode URLs can fall back to the SPA entry and be handled client-side. This approximates an nginx `try_files $uri /index.html` setup, although the HTTP status for those fallback responses is still 404 because GitHub Pages is static hosting.
+
 ## Pull Request Review
 
 The `Pull Request Review` workflow runs on pull requests that change chain configs, logos, workflows, or repository metadata. It validates chain configs and verifies that the explorer still builds.