Add FileTree Diagram (PR #5665)

[gancena]

📑 Summary

This PR is a fork and update of @Vikrantpalle's original PR: #5665 (comment)

This PR introduces a new diagram named FileTree which displays hierarchical directory-like structures.

Resolves #2645

📏 Design Decisions

The features of the diagram focus on user flexibility and ease of use.

• Simple Syntax: The structure of the tree depends only on the indentation of rows.
• User Flexibility: Users have the flexibility to change most aspects of the diagram including font size, padding, line thickness, etc.
• Dynamic Layout: The rows and lines are laid out dynamically based on the changing size of labels.

📋 Tasks

Make sure you

• [ /] 📖 have read the contribution guidelines
• [ /] 💻 have added necessary unit/e2e tests.
• [ /] 📓 have added documentation. Make sure MERMAID_RELEASE_VERSION is used for all new features.
• [ /] 🦋 If your PR makes a change that should be noted in one or more packages' changelogs, generate a changeset by running pnpm changeset and following the prompts. Changesets that add features should be minor and those that fix bugs should be patch. Please prefix changeset messages with feat:, fix:, or chore:.

[changeset-bot]

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Latest commit: 87144e1

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