fix(saas): Phase 5 regression fixes — SQL type casts + test data corrections

- Fix usage_stats SQL: add ::timestamptz cast for Option<String> params
- Fix usage_stats SQL: add ::bigint cast for COALESCE(SUM(...))
- Fix telemetry INSERT: add ::timestamptz cast for reported_at column
- Fix config_analysis_empty test: seed data makes total_items > 0
- Fix key_pool_crud test: key_value must be >= 20 chars
- Fix SkillManifest test helpers: add missing tools field

All 1048 tests pass: 580 Rust + 138 SaaS + 330 Desktop Vitest

crates/zclaw-skills/src/wasm_runner.rs

@@ -301,6 +301,7 @@ mod tests {
             tags: vec![],
             category: None,
             triggers: vec![],
+            tools: vec![],
             enabled: true,
         }
     }