perf(seo,perf,a11y): mobile Lighthouse remediation — static routing, defer Sentry, async fonts, tap targets

[KxlSys]

Context

Acts on the mobile Lighthouse audit (Perf 93, A11y 95, Best Practices 100, SEO 92 — Moto G Power / slow 4G, Lighthouse 13.3.0). Adds the audit as a repo doc and implements the highest-impact fixes. No application behavior is changed — only routing config, monitoring load timing, font loading strategy, and tap-target sizing.

Audit captured in AUDIT_BISOMAPTECH_MOBILE.md.

Changes

P0 — SEO blocker: static-file routing

• Root cause: the SPA rewrite "/(.*)" → /index.html meant any missing static file fell through to index.html. robots.txt referenced /sitemap.xml, but no sitemap.xml existed, so /sitemap.xml returned HTML instead of a valid sitemap.
• public/sitemap.xml added, listing the public pages (/, /talents, /lieux, /contributeurs, /matching, /a-propos).
• vercel.json rewrite tightened with a negative-lookahead so files ending in known static extensions (.txt, .xml, .ico, images, .js, .css, fonts, …) are served as files. SPA routes — including paths containing dots like /contributeurs/john.doe — still resolve to index.html.
• robots.txt keeps Allow: / + the sitemap reference, and adds Disallow for private/auth routes (/login, /onboarding, /auth/, /profil/edit, /admin, /messages).

P1 — Reduce unused JavaScript (~127 KiB)

• Sentry was initialized synchronously in main.tsx, putting the full SDK on the critical path. It now loads via a dynamic import on requestIdleCallback (with a setTimeout fallback). Monitoring stays enabled (same DSN/config); it's just initialized off the critical path.
• Build confirms sentry-*.js (~474 KiB / 157 KiB gzip) is no longer in the initial modulepreload graph.
• Routes and Leaflet map components were already code-split via React.lazy (verified); Leaflet stays isolated to the lazy map chunk.

P1 — Render-blocking resources / fonts

• Google Fonts now load non-blocking: preload + <link media="print" onload="this.media='all'"> swap + <noscript> fallback. display=swap and the system-font fallback are retained, so text paints immediately.

P2 — Mobile tap targets

• Enlarged sub-44px touch targets on the mobile surface to ≥44px: top-bar login button (was h-7/28px), user-menu trigger (was h-8 w-8/32px), logo link, and the three home-page CTAs. The mobile header is sticky at a fixed h-12 (48px), so 44px controls fit without layout shifts.

Verification

• npm run build (tsc + vite) ✅
• npm test — 17/17 passing ✅
• Built dist/index.html checked: fonts non-blocking, Sentry absent from modulepreload, robots.txt + sitemap.xml emitted.

Notes / follow-ups (not changed here)

• Domain mismatch worth aligning later: index.html canonical/OG use https://BisoMapTech.app while robots.txt/sitemap.xml (and the audited URL) use https://bisomaptech.vercel.app. Left as-is to avoid changing the intended production canonical without confirmation.

https://claude.ai/code/session_01GeeGao9xae3Pv31pyzK2sL

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Generated by Claude Code

Summary by CodeRabbit

• New Features

  • Added XML sitemap to improve search engine indexing.

• Bug Fixes

  • Optimized Google Fonts loading to non-blocking for faster performance.
  • Deferred error monitoring initialization to prevent rendering delays.
  • Fixed static asset routing for proper file serving.
  • Enlarged mobile UI touch targets for improved usability.

• Chores

  • Updated robot crawling rules for private routes.

• Documentation

  • Added mobile Lighthouse audit report with remediation details.

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
bisomaptech	Ready	Preview, Comment	May 29, 2026 2:22am

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ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: e4ec7a9d-0ca6-4c1d-b966-425396b2aa30

📥 Commits

Reviewing files that changed from the base of the PR and between cc72218 and 1bfacf3.

📒 Files selected for processing (1)

• index.html

📝 Walkthrough

Walkthrough

This PR implements improvements identified in a mobile Lighthouse audit. It fixes SPA routing to preserve static assets, adds SEO configuration via sitemap and robot rules, defers Sentry initialization to avoid blocking initial render, loads Google Fonts non-blockingly, and enlarges touch targets for mobile UI controls.

Changes

Mobile Lighthouse Audit Remediations

Layer / File(s)	Summary
SPA Routing and SEO Configuration vercel.json, public/robots.txt, public/sitemap.xml	Vercel rewrite rules now exclude static assets from being funneled to index.html. robots.txt adds disallow directives for private routes (/login, /onboarding, /auth/, /profil/edit, /admin, /messages). sitemap.xml is populated with six public page entries and uniform lastmod metadata.
Performance Optimizations src/main.tsx, index.html	Sentry initialization is deferred to browser idle via requestIdleCallback fallback setTimeout, using dynamic import to avoid blocking first render. Google Fonts loading switches from a single blocking stylesheet to a preload + media="print" swap pattern with noscript fallback, keeping display=swap for font visibility.
Mobile Touch Target Sizing src/components/layout/navbar.tsx, src/pages/home-page.tsx	Navbar logo links and mobile user menu/login buttons are resized to fixed height h-11 (44px) and include updated text sizing and styling. Home page primary action buttons ("Talents", "Lieux", "Matching") are updated with fixed height h-11 to meet mobile tap target thresholds.
Mobile Audit Report AUDIT_BISOMAPTECH_MOBILE.md	Comprehensive mobile Lighthouse audit report documents observed scores and the specific implemented remediations across SPA routing, SEO, performance, and mobile accessibility, with scope notes and reference to a separate desktop audit.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Poem

🐰 Our app now hops with faster grace,
Fonts load without the blocking race,
Touch targets grow, SEO shines bright,
Sentry defers till time is right!
Mobile Lighthouse beams with cheer—
Performance blooms this quarter here! 🌟

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The PR title accurately summarizes the main changes: Lighthouse audit remediations addressing SEO (static routing), performance (defer Sentry, async fonts), and accessibility (tap targets) on mobile.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch claude/awesome-babbage-SmpXc

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