chore(release): 0.8.1 — duplicate adopt/open fix + fuzz harness bookkeeping

- version 0.8.0 -> 0.8.1 (bug-fix release; semver-checks 196 pass vs 0.8.0)
- CHANGELOG 0.8.1: the manager_routing-found duplicate adopt/open fix,
  the fuzz harness, and the verification summary
- publish exclude gains docs/research/ (internal research notes;
  fuzz/ was already excluded — package verified clean of both)
- fuzzing.md §7.9: standing no-hosted-CI policy — corpus replay is the
  release-verification fuzz gate; campaigns manual via the detached
  runner; OSS-Fuzz out; no workflow files in this repo
- AGENTS.md: corpus replay added to the verification checklist
- lockfiles: alkcall 0.8.1 (root + fuzz)

Verification: 684 tests; clippy -D warnings (main, wasm, fuzz/shared);
fmt clean; doc clean; wasm32-unknown-unknown check+clippy clean;
semver-checks 196 pass; publish --dry-run 116 files (no fuzz/research/
reviews/sdd/AGENTS in the tarball); fuzz corpus replay 5/5 green

fuzz/Cargo.lock

@@ -27,7 +27,7 @@ dependencies = [
 
 [[package]]
 name = "alkcall"
-version = "0.8.0"
+version = "0.8.1"
 dependencies = [
  "async-trait",
  "bytes",