fix(renderer): preserve paragraph text color over fontRef

[0xez]

Summary

• Preserve paragraph-local defRPr text fills when a shape also supplies a
  fontRef color.
• Keep fontRef precedence over inherited list/master colors and over an empty
  paragraph defRPr.
• Add regression coverage for fontRefColor and table cellTextColor.

Fixes #21

Scope

• Bug fix
• Feature
• Docs
• Refactor
• Performance
• Security

Verification

• pnpm test
• pnpm build
• Manual check (synthetic PPTX)

Commands and key outputs:

pnpm exec vitest run test/unit/renderer/TextRenderer.branches.test.ts
  95 passed

pnpm test
  87 test files passed; 2794 tests passed

pnpm typecheck
pnpm lint
pnpm format:check
pnpm build
  all passed

Synthetic PPTX browser render:
  inline color:   rgb(36, 59, 83)
  computed color: rgb(36, 59, 83)

pnpm test:browser was not run because the matching Playwright browser binary
was not installed. The synthetic PPTX was rendered manually in an existing
Chromium instance instead.

Compatibility / Risk

• Breaking changes: none
• Risk areas: limited to the precedence decision between paragraph-local text
  fills and shape/table style color overrides. Run-local color and hyperlink
  decisions still use the existing run-specific state.

Security Impact

• No security impact
• Security relevant (describe threat/mitigation)

Docs

• README updated
• docs/* updated
• No doc updates needed

Release Notes

• Changelog updated
• Not user-facing change

[aiden0z]

Thanks for the focused fix. I verified the attached repro deck locally: the paragraph defRPr color now renders as #243B53 instead of being overridden by the shape's white fontRef, and the full unit suite passes.

Before we merge, could you please add one cross-layer regression in ShapeRenderer.test.ts? The new tests currently call renderTextBody(..., { fontRefColor }) directly, so they don't protect the production path that resolves p:style > a:fontRef in ShapeRenderer and passes it into text rendering. A single shape-level case containing both the white fontRef and the paragraph defRPr would be enough; the existing TextRenderer cases already cover the inverse cases.

One small documentation nit: the color-priority comment around TextRenderer.ts:1282 says paragraph/run color wins over the hyperlink theme, but hyperlink post-processing can still override a paragraph color. Please align the comment with the current behavior; no hyperlink behavior change is needed without a separate repro.

Once those two small items are addressed, this should be ready to merge. Thanks!

[0xez]

Thanks for the review — both requested items are now addressed.

• Added a cross-layer regression in ShapeRenderer.test.ts that parses a shape with a white p:style > a:fontRef and an explicit paragraph defRPr color (#243B53), renders it through renderShape(), and verifies that the production path keeps rgb(36, 59, 83).
• Aligned the TextRenderer color-priority comment with the existing hyperlink post-processing behavior. No hyperlink behavior was changed.

I also updated the branch with the latest main and resolved the overlapping CHANGELOG.md / TextRenderer.ts conflicts by retaining the upstream implementation and its accurate hyperlink comment. The PR now merges cleanly at head 830e96c.

Verification completed successfully on the updated branch:

• Targeted renderer tests: 311 passed
• Full unit suite: 93 test files, 2,986 tests passed
• pnpm typecheck
• pnpm lint
• pnpm format:check
• pnpm build

Thanks again for the precise feedback.

[aiden0z]

The requested production-path regression and the resulting color-precedence behavior are now present on main in 9a4ba71 for v1.3.0. Paragraph defRPr correctly wins over shape fontRef, while explicit run color remains highest priority. Native cases 0056-0059 cover the precedence and fallback matrix at SSIM 0.9908-0.9952, and CI is green.

Because the released implementation now contains equivalent or broader coverage, I am closing this PR as incorporated rather than treating it as abandoned. Thank you @0xez for following up and adding the cross-layer regression.