Address Gradle 9.6 deprecations, prune stale reports/tasks, and proofread docs

.agents/memory/MEMORY.md

@@ -15,6 +15,7 @@ See [README.md](README.md) for the format and routing rules.
 - [porting-buildsrc-from-consumer-repos](project/porting-buildsrc-from-consumer-repos.md) — To back-port buildSrc improvements from a consumer repo, diff after its last "Update `config`" commit; consumer-owned files never port.
 - [config-build-verification](project/config-build-verification.md) — config root has no `build` task; verify buildSrc via `./gradlew :buildSrc:test detekt` with JAVA_HOME exported.
 - [plugin-testkit-assertions-live-in-tool-base](project/plugin-testkit-assertions-live-in-tool-base.md) — Generic Gradle-plugin functional-test assertions (testkit-truth) belong in tool-base/plugin-testlib, not per-plugin `*-testlib` modules.
+- [gradle-10-third-party-deprecations](project/gradle-10-third-party-deprecations.md) — Two Gradle 9.6 deprecation nags come from Detekt and Gradle Doctor (not our build logic) — don't chase them in `buildSrc`; Kover's was fixed by bumping to 0.9.9.
 
 ## Reference (external systems)
 

.agents/memory/project/gradle-10-third-party-deprecations.md

@@ -0,0 +1,44 @@
+---
+name: gradle-10-third-party-deprecations
+description: Two Gradle 9.6 deprecation nags come from Detekt and Gradle Doctor, not our build logic — don't chase them in `buildSrc`. (Kover's was fixed by bumping to 0.9.9.)
+metadata:
+  type: project
+  since: 2026-07-02
+---
+
+Building with `--warning-mode all` on Gradle 9.6.1 still prints two
+deprecation warnings that originate in third-party plugins, not in
+`buildSrc`. Both become hard errors in Gradle 10:
+
+- `ReportingExtension.file(String)` — Detekt 1.23.8
+  (`DetektPlugin.apply`). Fixed on `main`, but maintainers state no
+  further 1.23.x releases are planned; the fix ships with Detekt 2.0
+  (alpha as of 2026-07, new plugin ID `dev.detekt`).
+  See [detekt#8452][detekt-8452].
+- `Project.getProperties` — Gradle Doctor 0.12.1
+  (`RemoteCacheEstimation`); no newer release available and no upstream
+  issue filed as of 2026-07.
+
+A third nag — Kover's "Using a Project object as a dependency notation"
+(`PrepareKover.kt`) — is **resolved**: Kover 0.9.9 fixes it
+([kotlinx-kover#818][kover-818], released 2026-07-17), and this branch
+bumped `Kover.version` 0.9.8 → 0.9.9. Verified by building `buildSrc`
+with `--warning-mode all`: the warning is present at 0.9.8 and gone at
+0.9.9.
+
+**Why:** branch `address-gradle-deprecations` removed every deprecated
+usage from our own build logic (Kotlin DSL delegated accessors,
+`PropertyDelegate`). The residual nags mislead agents into "fixing" our
+scripts or bumping plugins to pre-releases. Safety rules forbid
+auto-updating dependencies outside a dedicated update task, and the
+`dependency-update` skill rejects pre-releases.
+
+**How to apply:** treat these two warnings as known and out of our hands
+at the versions currently pinned; do not chase them in `buildSrc`.
+Re-check upstream during each `dependency-update` run: Detekt 2.0 final
+(mind the plugin ID change and config migration) and Gradle Doctor
+> 0.12.1. Remove this memory once both are resolved. Before Gradle 10,
+these must be resolved or the plugins dropped.
+
+[detekt-8452]: https://github.com/detekt/detekt/issues/8452
+[kover-818]: https://github.com/Kotlin/kotlinx-kover/issues/818

.agents/memory/reference/cache-warm-window.md

@@ -18,7 +18,7 @@ same cache slot — provided they fall within the TTL.
 Developers must have `ENABLE_PROMPT_CACHING_1H=1` set, otherwise the
 window is too short for cross-session hits to occur reliably.
 This setting will work ONLY for Claude Code which runs the CLI binary.
-It will not work for JetBrains Air or any other IDE plugin which does not
+It will not work for JetBrains Air or any other IDE plugin that does not
 run the Claude Code CLI binary.
 
 **Cache is per Anthropic workspace.** All developers authenticated via the