fix: repair configured plugin installs (#76129)

Summary:
- The PR adds a 2026.5.2 doctor repair pass for actively used configured downloadable plugins, prefers ClawHub ... pm fallback, records installed plugin state, extends upgrade-survivor coverage, and updates docs/changelog.
- Reproducibility: yes. Static inspection of current main and the PR head gives a high-confidence reproduction ... d-plugin install pass, while the PR tests the new repair-only path, success stamping, and warning behavior.

ClawSweeper fixups:
- Included follow-up commit: test: cover configured plugin install update path
- Included follow-up commit: test: isolate channel option metadata cache
- Included follow-up commit: fix: keep configured plugin repair scoped

Validation:
- ClawSweeper review passed for head d3519ce42c.
- Required merge gates passed before the squash merge.

Prepared head SHA: d3519ce42c
Review: https://github.com/openclaw/openclaw/pull/76129#issuecomment-4364120658

Co-authored-by: Peter Steinberger <steipete@gmail.com>

test/scripts/docker-e2e-plan.test.ts

@@ -353,6 +353,7 @@ describe("scripts/lib/docker-e2e-plan", () => {
       "published-upgrade-survivor-2026.4.29-feishu-channel",
       "published-upgrade-survivor-2026.4.29-bootstrap-persona",
       "published-upgrade-survivor-2026.4.29-plugin-deps-cleanup",
+      "published-upgrade-survivor-2026.4.29-configured-plugin-installs",
       "published-upgrade-survivor-2026.4.29-tilde-log-path",
       "published-upgrade-survivor-2026.4.29-versioned-runtime-deps",
     ]);
@@ -370,11 +371,13 @@ describe("scripts/lib/docker-e2e-plan", () => {
       "published-upgrade-survivor-2026.4.29-feishu-channel",
       "published-upgrade-survivor-2026.4.29-bootstrap-persona",
       "published-upgrade-survivor-2026.4.29-plugin-deps-cleanup",
+      "published-upgrade-survivor-2026.4.29-configured-plugin-installs",
       "published-upgrade-survivor-2026.4.29-tilde-log-path",
       "published-upgrade-survivor-2026.4.29-versioned-runtime-deps",
       "published-upgrade-survivor-2026.3.13",
       "published-upgrade-survivor-2026.3.13-feishu-channel",
       "published-upgrade-survivor-2026.3.13-bootstrap-persona",
+      "published-upgrade-survivor-2026.3.13-configured-plugin-installs",
       "published-upgrade-survivor-2026.3.13-tilde-log-path",
       "published-upgrade-survivor-2026.3.13-versioned-runtime-deps",
     ]);