feat(bundler-utils,vite-plugin): serve and cache variants via the core cache storage

[dangreen]

Wires the core SrcSetCacheStorage into the bundler integrations.

• @srcset/vite-plugin: the plugin instantiates the storage in the Vite cache directory and passes it via the cache generator option - variants are memoized inside the generator. The dev middleware streams variants from the storage by plain file name, anchored under the configured base; the cache: boolean option can disable caching for builds, the dev server always uses the storage
• @srcset/bundler-utils: createPlaceholder memoizes the placeholder via cache.memo as a .placeholder-postfixed variant; parseResourceQuery accepts the query with or without the leading ?; the module id is split once per load
• Reviewed locally in four Codex passes (final pass: no findings)

🤖 Generated with Claude Code

[coveralls]

Coverage Report for CI Build 31116733530

Coverage increased (+0.7%) to 89.111%

Details

• Coverage increased (+0.7%) from the base build.
• Patch coverage: 48 of 48 lines across 5 files are fully covered (100%).
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	537
Covered Lines:	494
Line Coverage:	91.99%
Relevant Branches:	363
Covered Branches:	308
Branch Coverage:	84.85%
Branches in Coverage %:	Yes
Coverage Strength:	97177.42 hits per line

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💛 - Coveralls