Feature/7078 make changes to allow for decimal values for sequence numbers

[milesspencer35]

📑 Summary

Added support for sequence numbers in sequence diagrams to use decimal values up to the hundredths place, and enabled incrementing using decimal values to the same precision. Other PR had issues, so this is a new one.

Resolves #7078

📏 Design Decisions

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

• Updated the Jison parser for sequence diagrams to accept decimal values to the hundredths place.
• Updated how the sequenceIndex and sequenceIndexStep are added to remove floating-point errors.
• Decrease the font size once a sequence number gets sufficiently long and spills out of the circle. I decided this was the best course of action because it was a simple fix for a rare use case.

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• 📖 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.
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🦋 Changeset detected

Latest commit: 50b2166

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

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commit: 50b2166

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Codecov Report

❌ Patch coverage is 0% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 3.55%. Comparing base (717d3b3) to head (50b2166).
⚠️ Report is 136 commits behind head on develop.

Files with missing lines	Patch %	Lines
.../mermaid/src/diagrams/sequence/sequenceRenderer.ts	0.00%	9 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           develop   #7174      +/-   ##
==========================================
- Coverage     3.55%   3.55%   -0.01%     
==========================================
  Files          474     473       -1     
  Lines        47453   47504      +51     
  Branches       730     731       +1     
==========================================
  Hits          1687    1687              
- Misses       45766   45817      +51     

Flag	Coverage Δ
unit	3.55% <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
.../mermaid/src/diagrams/sequence/sequenceRenderer.ts	0.06% <0.00%> (-0.01%)	⬇️

... and 13 files with indirect coverage changes

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Build	Status	Details	Updated (UTC)
default (Inspect)	⚠️ Changes detected (Review)	1 added	Nov 18, 2025, 5:45 PM