ci(release): publish a self-packaged project-memory server asset (ADR-0011 §3)

[sipemu]

Summary

Increment 3 of self-packaging (ADR-0011): each release build folds examples/project-memory into a copy of the staged escurel-server (via the escurel-server pack from #323) and publishes an escurel-<ver>-<target>-project-memory archive next to the plain one — so a download (not just a local pack) boots a populated project-memory tenant.

• Linux + Windows get the bundled asset. macOS is omitted: appending after EOF invalidates a macOS code signature; the notarisable Mach-O reserved-segment variant is the remaining deferred follow-on (ADR-0011 §3b — it needs a macOS linker + codesign path).
• CI smoke-tests the bundled variant on each platform: boots it (dev mode, temp data dir, ephemeral ports) and asserts list_skills over /mcp shows the seeded project skill — proving the embedded corpus seeds and serves from the shipped binary.
• create-release already globs escurel-* archives, so the new asset attaches automatically.

Additive — the existing plain-binary asset and release path are unchanged.

Test plan

release.yml can't run locally, so it's validated by a workflow_dispatch dry-run on this branch (build + smoke + package, no release) before it's relied on for a tag. The underlying pack→run→serve mechanism is already covered by crates/escurel-server/tests/self_packaging.rs (merged in #323).

🤖 Generated with Claude Code

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