fix: HA checks resolve service targets over project network; persist checks (#13)

- Health checks for local services dialed 127.0.0.1 from inside the backend
  container — the host's published port is unreachable there. Service-bound
  checks now resolve the service's DNS name on its project network (backend
  joins on demand), falling back to the service's stored port. A resolver
  failure surfaces as TARGET_UNRESOLVED instead of a fake loopback probe.
- Checks lived only in memory: a backend restart silently deleted every
  configured health check. ha_health_checks table + write-through on
  add/update/tick and hydrate-on-boot, matching the scaling-policy pattern.
- sqlc schema.sql gained the runtime columns added by later migrations —
  the stale snapshot already caused one silently-dropped-column bug.
- OpenAPI: runtime response now documents ports and health fields; types
  regenerated.
- Buttons no longer wrap ("+ new project" rendered on two lines).

Verified live: service check probes whoami-web:80 via DNS → healthy;
check survives a backend restart and rehydrates.

Generated with [Devin](https://devin.ai)

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

app/frontend/src/index.css

@@ -1523,6 +1523,7 @@ textarea {
   background: var(--accent-primary); color: var(--accent-on);
   border: none; border-radius: 8px; padding: 9px 17px;
   font: 700 12px 'JetBrains Mono', monospace; cursor: pointer;
+  white-space: nowrap; flex-shrink: 0;
   transition: background 0.15s, transform 0.15s;
   box-shadow: 0 2px 12px rgba(180, 227, 74, 0.22);
 }
@@ -1534,6 +1535,7 @@ textarea {
   background: var(--surface-card); color: var(--text-secondary);
   border: 1px solid var(--border-subtle); border-radius: 8px; padding: 8px 16px;
   font: 600 12px 'JetBrains Mono', monospace; cursor: pointer; transition: 0.15s;
+  white-space: nowrap; flex-shrink: 0;
 }
 .v-btn-ghost:hover { color: var(--text-primary); border-color: var(--border-default); }