Add frontend autoformatting and set CI to require formatted code for all languages (#6052)

# Description of Changes
Changes the strategy for autoformatting to reject PRs if they are not
formatted correctly instead of allowing them to merge and then spawning
a new PR to fix the formatting. The old strategy just caused more work
for us because we'd have to manually approve the followup PR and get it
merged, which required 2 reviewers so in practice it rarely got done and
just meant everyone's PRs ended up containing reformatting for unrelated
files, which makes code review unnecessarily difficult. If the PR's code
is not formatted correctly after this PR, a comment will be added
automatically to tell the author how to run the formatter script to fix
their code so it can go in.

This also enables autoformatting for the frontend code, using Prettier.
I've enabled it for pretty much everything in the frontend folder, other
than 3rd party files and files it doesn't make sense for. I also
excluded Markdown because it sounds likely to be more annoying to have
to autoformat the Markdown in the frontend folder but nowhere else. Open
to changing this though if people disagree.

> [!note]
> 
> Advice to reviewers: The first commit contains all of the actual logic
I've introduced (CI changes, Prettier config, etc.)
> The second commit is just the reformatting of the entire frontend
folder.
> The first commit needs proper review, the second one just give it a
spot-check that it's doing what you'd expect.

.github/workflows/build.yml

@@ -50,6 +50,7 @@ jobs:
     permissions:
       actions: read
       security-events: write
+      pull-requests: write
     strategy:
       fail-fast: false
       matrix:
@@ -84,6 +85,60 @@ jobs:
           gradle-version: 9.3.1
           cache-disabled: true
 
+      - name: Check Java formatting (Spotless)
+        if: matrix.jdk-version == 25 && matrix.spring-security == false
+        id: spotless-check
+        run: ./gradlew spotlessCheck
+        continue-on-error: true
+        env:
+          MAVEN_USER: ${{ secrets.MAVEN_USER }}
+          MAVEN_PASSWORD: ${{ secrets.MAVEN_PASSWORD }}
+          MAVEN_PUBLIC_URL: ${{ secrets.MAVEN_PUBLIC_URL }}
+
+      - name: Comment on Java formatting failure
+        if: steps.spotless-check.outcome == 'failure'
+        uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8.0.0
+        with:
+          script: |
+            const marker = '<!-- java-formatting-check -->';
+            const body = [
+              marker,
+              '### Java Formatting Check Failed',
+              '',
+              'Your code has formatting issues. Run the following command to fix them:',
+              '',
+              '```bash',
+              './gradlew spotlessApply',
+              '```',
+              '',
+              'Then commit and push the changes.',
+            ].join('\n');
+            const { data: comments } = await github.rest.issues.listComments({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              issue_number: context.issue.number,
+            });
+            const existing = comments.find(c => c.body.includes(marker));
+            if (existing) {
+              await github.rest.issues.updateComment({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                comment_id: existing.id,
+                body,
+              });
+            } else {
+              await github.rest.issues.createComment({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                issue_number: context.issue.number,
+                body,
+              });
+            }
+
+      - name: Fail if Java formatting issues found
+        if: steps.spotless-check.outcome == 'failure'
+        run: exit 1
+
       - name: Build with Gradle and spring security ${{ matrix.spring-security }}
         run: ./gradlew build -PnoSpotless
         env:
@@ -187,6 +242,9 @@ jobs:
     if: needs.files-changed.outputs.frontend == 'true'
     needs: files-changed
     runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      pull-requests: write
     steps:
       - name: Harden Runner
         uses: step-security/harden-runner@58077d3c7e43986b6b15fba718e8ea69e387dfcc # v2.15.1
@@ -202,6 +260,52 @@ jobs:
           cache-dependency-path: frontend/package-lock.json
       - name: Install frontend dependencies
         run: cd frontend && npm ci
+      - name: Check TypeScript formatting (Prettier)
+        id: prettier-check
+        run: cd frontend && npm run format:check
+        continue-on-error: true
+      - name: Comment on TypeScript formatting failure
+        if: steps.prettier-check.outcome == 'failure'
+        uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8.0.0
+        with:
+          script: |
+            const marker = '<!-- typescript-formatting-check -->';
+            const body = [
+              marker,
+              '### TypeScript Formatting Check Failed',
+              '',
+              'Your code has formatting issues. Run the following command to fix them:',
+              '',
+              '```bash',
+              'cd frontend && npm run fix',
+              '```',
+              '',
+              'Then commit and push the changes.',
+            ].join('\n');
+            const { data: comments } = await github.rest.issues.listComments({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              issue_number: context.issue.number,
+            });
+            const existing = comments.find(c => c.body.includes(marker));
+            if (existing) {
+              await github.rest.issues.updateComment({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                comment_id: existing.id,
+                body,
+              });
+            } else {
+              await github.rest.issues.createComment({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                issue_number: context.issue.number,
+                body,
+              });
+            }
+      - name: Fail if TypeScript formatting issues found
+        if: steps.prettier-check.outcome == 'failure'
+        run: exit 1
       - name: Type-check frontend
         run: cd frontend && npm run prep && npm run typecheck:all
       - name: Lint frontend

.github/workflows/pre_commit.yml

@@ -2,7 +2,7 @@ name: Pre-commit
 
 on:
   workflow_dispatch:
-  push:
+  pull_request:
     branches:
       - main
 
@@ -16,9 +16,6 @@ jobs:
       # Prevents sdist builds → no tar extraction
       PIP_ONLY_BINARY: ":all:"
       PIP_DISABLE_PIP_VERSION_CHECK: "1"
-    permissions:
-      contents: write
-      pull-requests: write
     steps:
       - name: Harden Runner
         uses: step-security/harden-runner@58077d3c7e43986b6b15fba718e8ea69e387dfcc # v2.15.1
@@ -31,13 +28,6 @@ jobs:
           fetch-depth: 0
           persist-credentials: false
 
-      - name: Setup GitHub App Bot
-        id: setup-bot
-        uses: ./.github/actions/setup-bot
-        with:
-          app-id: ${{ secrets.GH_APP_ID }}
-          private-key: ${{ secrets.GH_APP_PRIVATE_KEY }}
-
       - name: Set up Python
         uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6.2.0
         with:
@@ -57,47 +47,4 @@ jobs:
           pre-commit run gitleaks --all-files -c .pre-commit-config.yaml
           pre-commit run end-of-file-fixer --all-files -c .pre-commit-config.yaml
           pre-commit run trailing-whitespace --all-files -c .pre-commit-config.yaml
-        continue-on-error: true
-
-      - name: Set up JDK 25
-        uses: actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654 # v5.2.0
-        with:
-          java-version: "25"
-          distribution: "temurin"
-
-      - name: Setup Gradle
-        uses: gradle/actions/setup-gradle@f29f5a9d7b09a7c6b29859002d29d24e1674c884 # v5.0.1
-        with:
-          gradle-version: 9.3.1
-
-      - name: Build with Gradle
-        run: ./gradlew build
-        env:
-          MAVEN_USER: ${{ secrets.MAVEN_USER }}
-          MAVEN_PASSWORD: ${{ secrets.MAVEN_PASSWORD }}
-          MAVEN_PUBLIC_URL: ${{ secrets.MAVEN_PUBLIC_URL }}
-
-      - name: git add
-        run: |
-          git add .
-          git diff --staged --quiet || echo "CHANGES_DETECTED=true" >> $GITHUB_ENV
-
-      - name: Create Pull Request
-        if: env.CHANGES_DETECTED == 'true'
-        uses: peter-evans/create-pull-request@c0f553fe549906ede9cf27b5156039d195d2ece0 # v8.1.0
-        with:
-          token: ${{ steps.setup-bot.outputs.token }}
-          commit-message: ":file_folder: pre-commit"
-          committer: ${{ steps.setup-bot.outputs.committer }}
-          author: ${{ steps.setup-bot.outputs.committer }}
-          signoff: true
-          branch: pre-commit
-          title: "🤖 format everything with pre-commit by ${{ steps.setup-bot.outputs.app-slug }}"
-          body: |
-            Auto-generated by [create-pull-request][1] with **${{ steps.setup-bot.outputs.app-slug }}**
-
-            [1]: https://github.com/peter-evans/create-pull-request
-          draft: false
-          delete-branch: true
-          labels: github-actions
-          sign-commits: true
+          git diff --exit-code