refactor(db): port sleep/wake sweeper to sqlc (#81)

Tranche 7 — all 11 raw sites in sleeper.go. Adds sleep_enabled and
sleep_idle_minutes to schema.sql and three runtime.sql queries:
ListSleepCandidates, GetServiceDomainText, GetServiceStatusText. Status
writes reuse SetServiceStatus; the wake loader reuses
GetServiceRuntimeWithOwner (the projects join is FK-safe).

Also drops a dead port read in handleServiceSleep that was loaded but
never used.

TestRuntimeLiveInvariants now covers the sweep filter and both text
lookups on live Postgres.

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Co-authored-by: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

app/backend/sqlc/schema.sql

@@ -69,6 +69,8 @@ CREATE TABLE services (
     static_dir VARCHAR(255) NOT NULL DEFAULT '',
     node_id VARCHAR(255),
     spread BOOLEAN NOT NULL DEFAULT false,
+    sleep_enabled BOOLEAN NOT NULL DEFAULT false,
+    sleep_idle_minutes INTEGER NOT NULL DEFAULT 15,
     placement_tags JSONB NOT NULL DEFAULT '[]',
     traefik_labels JSONB NOT NULL DEFAULT '{}'
 );