[AlexAndBear]

Description

This enhancement adds missing text alignment support to the tiptap-json content strategy so it matches the editor capabilities already available in other rich-text strategies.

Changes made:

• Added TextAlign extension to tiptap-json strategy with heading and paragraph support
• Added text-align action group (align-left, align-center, align-right, align-justify) to the tiptap-json strategy toolbar actions
• Extended unit tests to verify extension registration and text-align actions
• Updated JSON serialize test expectation to include attrs.textAlign: null on paragraph nodes

Related Issue

• Fixes N/A

How Has This Been Tested?

• test environment: local development environment (macOS), pnpm + Vitest
• test case 1: verify tiptap-json strategy includes textAlign extension
• test case 2: verify text-align group exposes all four alignment actions
• test case 3: verify serialization output for paragraph includes textAlign attribute
• pnpm test:unit --run packages/web-pkg/tests/unit/editor/strategies/tiptapJson.spec.ts

Types of changes

• Bugfix
• Enhancement (a change that doesn't break existing code or deployments)
• Breaking change (a modification that affects current functionality)
• Technical debt (addressing code that needs refactoring or improvements)
• Tests (adding or improving tests)
• Documentation (updates or additions to documentation)
• Maintenance (like dependency updates or tooling adjustments)