greenfield: clean slate for ALPN-as-service pivot
Delete old source crates (alknet-core, alknet, alknet-napi), old
architecture docs (ADRs, specs, open questions), old research docs
(phase2, event-sourcing, feasibility, etc.), old tasks, and obsolete
reference material (gitserver/MPL, honker, nats, rustfs, polyglot,
keystone, distributed-identity).
Keep: alknet-secret (standalone, compiles), pivot docs, iroh and ssh
references, rudolfs reference (MIT/Apache, fork candidate), ops docs,
sdd_process.md, and licenses.
Previous implementation preserved at /workspace/@alkdev/alknet-main/
for reference during porting.
Workspace compiles: cargo check + 14 tests pass for alknet-secret.