Fix markdown labels for flowcharts

[darshanr0107]

📑 Summary

Restores the behavior that only nodes and edges delimited with double-quote-backtick (e.g. node["_markdown_ **text**"]) are processed as markdown.

Resolves #6275, #6048, and #5824

This PR is based upon #6345

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Latest commit: cf12603

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This PR includes changesets to release 1 package

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mermaid	Patch

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commit: cf12603

[codecov]

Codecov Report

❌ Patch coverage is 0% with 249 lines in your changes missing coverage. Please review.
✅ Project coverage is 3.56%. Comparing base (d5bc07d) to head (cf12603).

Files with missing lines	Patch %	Lines
...c/rendering-util/rendering-elements/createLabel.js	0.00%	70 Missing ⚠️
...aid/src/rendering-util/rendering-elements/edges.js	0.00%	51 Missing ⚠️
...-util/rendering-elements/shapes/labelImageUtils.ts	0.00%	42 Missing ⚠️
...c/rendering-util/rendering-elements/shapes/util.ts	0.00%	27 Missing ⚠️
.../src/rendering-util/rendering-elements/clusters.js	0.00%	23 Missing ⚠️
packages/mermaid/src/diagrams/flowchart/flowDb.ts	0.00%	16 Missing ⚠️
...ng-util/rendering-elements/shapes/rectWithTitle.ts	0.00%	9 Missing ⚠️
.../rendering-util/rendering-elements/shapes/erBox.ts	0.00%	6 Missing ⚠️
packages/mermaid/src/dagre-wrapper/shapes/util.js	0.00%	2 Missing ⚠️
packages/mermaid/src/diagrams/kanban/kanbanDb.ts	0.00%	2 Missing ⚠️
... and 1 more

Additional details and impacted files

@@            Coverage Diff             @@
##           develop   #7057      +/-   ##
==========================================
- Coverage     3.57%   3.56%   -0.01%     
==========================================
  Files          473     475       +2     
  Lines        47475   47570      +95     
  Branches       734     735       +1     
==========================================
  Hits          1696    1696              
- Misses       45779   45874      +95     

Flag	Coverage Δ
unit	3.56% <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/diagrams/flowchart/types.ts	100.00% <ø> (ø)
...kages/mermaid/src/diagrams/mindmap/mindmapTypes.ts	100.00% <ø> (ø)
packages/mermaid/src/types.ts	100.00% <ø> (ø)
packages/mermaid/src/diagrams/mindmap/mindmapDb.ts	0.00% <0.00%> (ø)
packages/mermaid/src/dagre-wrapper/shapes/util.js	0.00% <0.00%> (ø)
packages/mermaid/src/diagrams/kanban/kanbanDb.ts	0.00% <0.00%> (ø)
.../rendering-util/rendering-elements/shapes/erBox.ts	0.00% <0.00%> (ø)
...ng-util/rendering-elements/shapes/rectWithTitle.ts	0.78% <0.00%> (-0.04%)	⬇️
packages/mermaid/src/diagrams/flowchart/flowDb.ts	0.00% <0.00%> (ø)
.../src/rendering-util/rendering-elements/clusters.js	0.00% <0.00%> (ø)
... and 4 more

... and 1 file with indirect coverage changes

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Build	Status	Details	Updated (UTC)
default (Inspect)	⚠️ Changes detected (Review)	271 changed, 3 added	Dec 26, 2025, 12:49 PM