Second pass with the avoid-ai-writing detector

The skill's detector scored the README, PARITY.md and the extracted
comment prose. Fixed what it flagged: hollow intensifiers, "in order
to", "additionally", "the whole point", bold sentences in docs, and
bold that had wrapped across comment lines. Comment prose scores a
maximum of 4 out of 100 across the repo.

One sweep rule mangled four comments ("which is the entire point of X"
lost its clause); repaired, and the rule now keeps the clause.

Comments and strings only. 1208 tests pass, counted from the XML.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

engine/src/test/kotlin/io/flamenet/e2e/DisappearingTest.kt

@@ -9,7 +9,7 @@ import kotlin.test.assertTrue
 /**
  * Disappearing messages (§6.11), at the vault.
  *
- * Expiry runs on read, and that is the point. A sweep on a timer leaves
+ * Expiry runs on read. A sweep on a timer leaves
  * expired messages on disk between runs, and a "disappearing" message still
  * sitting in the vault is a claim rather than a feature. Reading is the one
  * path every caller shares.