docs: add missing REST API examples to README

[hawk-roy]

Summary

This PR supplements the README REST API section with the routes that are already registered in router.go but were not previously documented as examples.

Changes

• Add health check example: /api/v1/health
• Add stats example: /api/v1/stats
• Add author detail example: /api/v1/authors/:id
• Add dynasty detail example: /api/v1/dynasties/:id
• Add poetry type list example: /api/v1/types
• Add poetry type detail example: /api/v1/types/:id

Why

The README should reflect the currently available REST routes so users can discover and test the full API surface more easily.

Scope

• Documentation only
• No code or behavior changes

Verification

• Cross-checked the README REST API examples against the routes registered in router.go

[codecov-commenter]

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Additional details and impacted files

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Flag	Coverage Δ
unittests	14.98% <ø> (?)

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[palemoky]

Good job! Thanks for your contribution!