fix(homecore-recorder/sec): bump sqlx 0.7.4 → 0.8.1+ (RUSTSEC, audit HC-medium)

Per iter-10 security audit (docs/security/HOMECORE-security-audit-iter10.md):
sqlx 0.7.4 ships an advisory for binary protocol misinterpretation.
Bump to 0.8.1+ — cargo resolved to 0.8.6.

Feature set unchanged (default-features = false +
runtime-tokio-native-tls, sqlite, chrono, uuid). Tests still pass:

  cargo test -p homecore-recorder --features ruvector
  → 20 passed; 0 failed

No code changes required. The 0.7 → 0.8 API surface we touch in
`db.rs` is stable across the bump.

Deferred to a later iter:
- shlex 0.1.1 → ≥1.3.0 (transitive via wasm3-sys, only on
  --features wasm3 which is default-off; will be addressed when
  the wasm3 path is removed per ADR-128 Q2 Wasmtime resolution)
- wasmtime 25 → 36+/42+ (HC-03/04 CVSS 9.0 sandbox-escape) — being
  handled by a background coder agent this iter, separate commit.

Refs: docs/security/HOMECORE-security-audit-iter10.md (HC-09 sqlx)
Refs: #798

Co-Authored-By: claude-flow <ruv@ruv.net>

v2/crates/homecore-recorder/Cargo.toml

@@ -32,7 +32,7 @@ homecore = { path = "../homecore", version = "0.1.0-alpha.0" }
 tokio = { version = "1", features = ["sync", "rt", "rt-multi-thread", "time", "macros"] }
 
 # SQLite via sqlx — only the lite feature set; no postgres, no tls
-sqlx = { version = "0.7", default-features = false, features = [
+sqlx = { version = "0.8.1", default-features = false, features = [
     "runtime-tokio-native-tls",
     "sqlite",
     "chrono",