Make the Post Title block name more distinguishable

[snehapatil2001]

Issue: #62177

What?

• Fixes issue where block names were ambiguous across languages by renaming "Title" block to "Post Title".

Why?

• The current naming convention led to confusion, especially in languages where "Title" and "Heading" are translated similarly, causing accessibility issues for screen reader users.
• This PR aims to clarify the distinction between "Title" and "Heading" blocks across languages, improving usability and accessibility.

How?

• Updated block registration settings to change the name of the "Title" block to "Post Title".
• This change ensures consistency and clarity in block naming, making it easier for users and translators to differentiate between the two block types.

Testing Instructions

1. Set WordPress admin interface to various languages: Italian, Portuguese, Swedish, Russian, Chinese.
2. Open a post or page editor.
3. Insert both "Post Title" and "Heading" blocks.
4. Verify that the block names are correctly translated and distinguishable in each language.
5. Test accessibility with screen readers to ensure proper announcement of block names.

Testing Instructions for Keyboard

1. Navigate to the block inserter using keyboard navigation.
2. Insert "Post Title" and "Heading" blocks.
3. Verify that the keyboard shortcuts and navigation paths are intuitive and accessible.

Screenshots or Screencast

[github-actions]

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Co-authored-by: snehapatil2001 <snehapatil02@git.wordpress.org>
Co-authored-by: Mamaduka <mamaduka@git.wordpress.org>

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[github-actions]

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[Mamaduka]

Thanks for contributing, @snehapatil2001!

I think the linked issue needs a decision before it's actionable. The Title block can be used with various post types, which is why the name was made generic. See: #50147.