chore: update documentation dependency to caret range in plugin-api-docgen

[Copilot]

Updates documentation dependency from exact version to caret range to align with monorepo conventions.

Changes

• packages/plugin-api-docgen/package.json: "14.0.3" → "^14.0.3"
• Updated lockfile
• Added changeset

Most dependencies in the monorepo use caret ranges. This change standardizes the documentation dependency while maintaining the current version (14.0.3, latest available).

Original prompt

更新 plugin-api-docgen 中 documentation 的版本

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