SEO Starter Kit

Act as a technical SEO specialist for small Indian businesses. I'll paste my website's HTML at the end. Improve it for search engines and social sharing WITHOUT changing the design or the visible text, then give me the updated file.

MY BUSINESS
- Name: [Your business name]
- Area & city: [Your area, city]
- Website URL: [Your website URL]
- Phone: [Your WhatsApp number]

DO ALL OF THE FOLLOWING
1. Write a <title> (50–60 characters) and a meta description (140–155 characters) that naturally say what I do and where
2. Add a canonical link, the viewport meta tag, the lang attribute and a favicon link placeholder
3. Add Open Graph and Twitter card tags (title, description, URL, a 1200×630 image, site name, locale en_IN) so links look good on WhatsApp, Facebook and LinkedIn
4. Add LocalBusiness JSON-LD (choose the most specific schema.org type for my business) with name, address, phone, URL, opening hours, a geo placeholder and priceRange
5. Fix the heading structure (exactly one H1, logical H2/H3), add missing alt text to images and descriptive aria-labels to icon-only links and buttons
6. Add loading="lazy" plus width and height to below-the-fold images to prevent layout shift
7. Create a robots.txt and a sitemap.xml for my site in separate code blocks

THEN
- Show a checklist of every change with ✓ marks
- Show a "search result preview" (title, URL, description) and a "WhatsApp share preview" in plain text
- Suggest 5 local keywords to use naturally in my page copy

Here is my HTML:
[PASTE YOUR HTML HERE]