Wire up contain: layout and contain: paint to Taffy

[nicoburns]

Summary

Updates Taffy to a revision that includes the new contain style (DioxusLabs/taffy#1128) and wires up Stylo's computed contain to it:

• stylo_taffy::convert::contain(input: stylo::Contain, display: stylo::Display) -> taffy::Contain maps the LAYOUT and PAINT flags (other flags have no Taffy layout effect). Containment is not applied to non-atomic inline-level boxes (display: inline with inside: flow), per css-contain-1's applicability rules.
• TaffyStyloStyle implements the new CoreStyle::contain() accessor, and the eager to_taffy_style conversion sets contain as well.
• compute_layout_damage in blitz-dom now treats a change to contain as requiring box-tree rebuild, since containment changes formatting-context structure (float containment, margin collapsing).

WPT css/css-contain results: 248 tests passing vs 239 on main (+11 newly passing: independent formatting context, float containment, margin collapsing, and baseline suppression tests; -2: contain-layout-dynamic-004/005.html, which require JavaScript to apply containment dynamically and previously only passed vacuously because both test and ref rendered without containment).

Link to Devin session: https://dioxus.staging.devinenterprise.com/sessions/c903534a83f54a6daf2f68f4cc38cf72
Requested by: @nicoburns

WPT results

11 newly passing, 2 newly failing (net +9).

Full diff (13 changed tests)

+ Fail => Pass css/css-contain/contain-content-001.html
+ Fail => Pass css/css-contain/contain-content-002.html
- Pass => Fail css/css-contain/contain-layout-dynamic-004.html
- Pass => Fail css/css-contain/contain-layout-dynamic-005.html
+ Fail => Pass css/css-contain/contain-layout-formatting-context-float-001.html
+ Fail => Pass css/css-contain/contain-layout-formatting-context-margin-001.html
+ Fail => Pass css/css-contain/contain-layout-ifc-022.html
+ Fail => Pass css/css-contain/contain-layout-independent-formatting-context-001.html
+ Fail => Pass css/css-contain/contain-layout-suppress-baseline-002.html
+ Fail => Pass css/css-contain/contain-paint-formatting-context-float-001.html
+ Fail => Pass css/css-contain/contain-paint-formatting-context-margin-001.html
+ Fail => Pass css/css-contain/contain-paint-ifc-011.html
+ Fail => Pass css/css-contain/contain-paint-independent-formatting-context-001.html

_{Generated by the WPT workflow.}

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