Text is no longer a hand-written HTML effect (docs in
docs/zh/plans/text-footage-redesign.md):
- textv3 gains structured inputs - plain text, font family/size, font
color, outline (enable/color/width), glow (enable/color/radius); the
legacy text_in HTML is hidden and auto-migrated to plain text on load.
- Outline and glow render as GPU post-process chains (dilate/blur +
colorize under the text); the font color tints the raster
premultiplied. Plain text now rasterizes even with both passes off
(previously a null deferred job), fixing a use-after-free where the
handle was lifted out of an owning Option<NodeValue> before addref.
- A cosmic-text backend (the lockfile's 0.19) installs at engine
startup through the textbackend hooks and feeds the font-family combo.
- The project panel gains 添加文本素材 next to 新建序列: a text entry
in the bin that drops onto the timeline as a clip (one undo row), its
parameters shown as structured fields in the inspector (multiline
text area, no HTML anywhere). text3 is hidden from the effect add
menus; legacy text3 chains keep evaluating.