0.4.0 release line

0.4.0 release line (Plan 300)

Rust artifacts (crates.io):

• eggserve-primitives 0.2.2 (78fd797e45a374bfa419bc75f7e497653ce25e24cde0e771cc332e267f18355c)
• eggserve-server 0.4.0 (fb601019a2914ae99f264640b66c80496a67b7ea3315fd0809747d4f22327e40)
• eggserve-static 0.4.0 (c53bf2f2d92e660940676eb8b6bdff2ceae5ccaa8a056f14)
• eggserve-h3 0.4.0 (ee9b47c7ca050cea49c40eb1fe6489948948b6d666fc3b2386983ef333c55f8a)
• eggserve-core 0.4.0 (5cf75d63bdfbfa70a92c7884220addf032382099d3adabbd1bd38c0e798e48a7)
• eggserve-bin 0.2.2 (c2e325351425331e9d6b330b0edb1c73ef4a0fccba3e4a85df617dabb3db4e45)

Highlights: direct-Tower feature edge (tower no longer activates tower-layer; downstream Layer authors depend on tower-layer directly) and H1 response-trailer wire delivery via head-time TrailerDeclaration (undeclared H1 sources suppressed before polling). H2/H3 tiers unchanged. Registry-only consumer proof: direct, Tower/Axum, and core-compat fixtures pass against the exact published versions with a core/static/PHF-free direct graph.

Wheel: eggserve 0.2.4 ships the 0.4.0 Rust code via the release workflow (TestPyPI qualification, then PyPI).

Source: d537d4d. Hosted CI 36176532051 (rust, supply-chain, python) green. Evidence: plans/closure/direct-h1-runtime/300-release-0-4-0-publication.md.