fix: restore curve type configuration functionality for flowcharts

[ashishjain0512]

This pull request addresses the issue with curve type settings not being applied correctly for flowcharts in Mermaid. The changes include restoring the curve type configuration functionality and adding support for additional curve types.

Fixes and Enhancements:

• .changeset/curve-interpolation-fix.md: Documented the fix for restoring curve type configuration functionality for flowcharts. This ensures that curve type settings are applied correctly when configured through various methods.

Codebase Updates:

• packages/mermaid/src/config.type.ts: Expanded the curve property in FlowchartDiagramConfig to include additional curve types such as 'bumpX', 'bumpY', 'catmullRom', 'monotoneX', 'monotoneY', 'natural', 'step', 'stepAfter', and 'stepBefore'.
• packages/mermaid/src/diagrams/flowchart/flowDb.spec.ts: Added tests to verify that the default and edge-specific interpolation settings are applied correctly.

Implementation Details:

• packages/mermaid/src/diagrams/flowchart/flowDb.ts: Updated the FlowDB class to ensure that the interpolate property is correctly set for edges, and that the curve type is determined based on edge-specific or default settings. [1] [2]
• packages/mermaid/src/rendering-util/rendering-elements/edges.js: Imported additional curve functions from d3 and updated the insertEdge function to handle the new curve types. [1] [2]

Schema Update:

• packages/mermaid/src/schemas/config.schema.yaml: Updated the JSON schema to include the new curve types in the enum for flowchart curve configuration.

Resolves #6193

📏 Design Decisions

Describe the way your implementation works or what design decisions you made if applicable.

📋 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]

🦋 Changeset detected

Latest commit: f8e329f

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
mermaid	Minor

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[netlify]

✅ Deploy Preview for mermaid-js ready!

Name	Link
🔨 Latest commit	f8e329f
🔍 Latest deploy log	https://app.netlify.com/sites/mermaid-js/deploys/67e1beba604d4a0008b29c84
😎 Deploy Preview	https://deploy-preview-6408--mermaid-js.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[pkg-pr-new]

Open in Stackblitz

npm i https://pkg.pr.new/mermaid-js/mermaid@6408

npm i https://pkg.pr.new/mermaid-js/mermaid/@mermaid-js/mermaid-zenuml@6408

npm i https://pkg.pr.new/mermaid-js/mermaid/@mermaid-js/layout-elk@6408

npm i https://pkg.pr.new/mermaid-js/mermaid/@mermaid-js/parser@6408

commit: f8e329f

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 30 lines in your changes missing coverage. Please review.

Project coverage is 3.86%. Comparing base (9b9cec9) to head (f8e329f).
Report is 3 commits behind head on develop.

Files with missing lines	Patch %	Lines
...aid/src/rendering-util/rendering-elements/edges.js	0.00%	28 Missing ⚠️
packages/mermaid/src/diagrams/flowchart/flowDb.ts	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           develop   #6408      +/-   ##
==========================================
- Coverage     3.86%   3.86%   -0.01%     
==========================================
  Files          412     411       -1     
  Lines        43160   43178      +18     
  Branches       664     664              
==========================================
  Hits          1670    1670              
- Misses       41490   41508      +18     

Flag	Coverage Δ
unit	3.86% <0.00%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
packages/mermaid/src/config.type.ts	100.00% <ø> (ø)
packages/mermaid/src/diagrams/flowchart/flowDb.ts	0.00% <0.00%> (ø)
...aid/src/rendering-util/rendering-elements/edges.js	0.00% <0.00%> (ø)

... and 1 file with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[knsv]

Looks good!