chore: prettier format all files, brotli, Sentry release tagging, CI gates

Prettier: auto-formatted 103 files to fix baseline. Prettier check in CI
  is now a hard gate (removed continue-on-error).

Brotli: installed libnginx-mod-http-brotli-filter/static. Enabled in nginx
  with brotli_static on for pre-compressed assets and comp_level 6.

Sentry releases: deploy script now exports VITE_APP_VERSION=<git-short-sha>
  before building so each Sentry release maps to an exact commit.
  CI also passes github.sha as VITE_APP_VERSION.

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

.github/workflows/deploy-pull-request.yml

@@ -1,10 +1,10 @@
 name: Deploy PR to Netlify
-run-name: "Deploy PR to Netlify (${{ github.event.workflow_run.head_branch }})"
+run-name: 'Deploy PR to Netlify (${{ github.event.workflow_run.head_branch }})'
 
 on:
   workflow_run:
-      workflows: ["Build pull request"]
-      types: [completed]
+    workflows: ['Build pull request']
+    types: [completed]
 
 jobs:
   deploy-pull-request:
@@ -42,7 +42,7 @@ jobs:
         uses: nwtgck/actions-netlify@4cbaf4c08f1a7bfa537d6113472ef4424e4eb654 # v3.0.0
         with:
           publish-dir: dist
-          deploy-message: "Deploy PR ${{ steps.pr.outputs.id }}"
+          deploy-message: 'Deploy PR ${{ steps.pr.outputs.id }}'
           alias: ${{ steps.pr.outputs.id }}
           # These don't work because we're in workflow_run
           enable-pull-request-comment: false
@@ -59,5 +59,5 @@ jobs:
           pr-number: ${{ steps.pr.outputs.id }}
           comment-tag: ${{ steps.pr.outputs.id }}
           message: |
-              Preview: ${{ steps.netlify.outputs.deploy-url }}
-              ⚠️ Exercise caution. Use test accounts. ⚠️
+            Preview: ${{ steps.netlify.outputs.deploy-url }}
+            ⚠️ Exercise caution. Use test accounts. ⚠️