feat(services): builder selection, resource reservations, static builder (C3)

services.builder picks the build strategy per service: auto detects from
repo contents (Dockerfile → railpack → nixpacks), explicit overrides force
a builder, and static builds assets in a node stage then serves them from
an nginx image (static_build_cmd/static_dir, port 80 default).

- cpu_reserve/memory_reserve → Docker CPU shares + MemoryReservation;
  cpu/memory stay hard caps (NanoCPUs/Memory). Empty string clears.
- app_settings.default_cpu/default_memory override service-create
  fallbacks; capacity_policy=block fails deploys whose requested memory
  exceeds node capacity (default warn logs via slog).
- Resource specs are validated — "512mb" fails instead of silently
  dropping the limit.
- Fixes: deployments.go hardcoded nixpacks (auto-detect was dead code);
  DockerfileBuilder passed the Dockerfile *path* as build-context content;
  BuildImage never drained the daemon stream so builds could abort and
  errors went unseen — stream is now consumed and errorDetail surfaced.
- CLI: --builder/--cpu-reserve/--memory-reserve/--static-cmd/--static-dir
  on create+update; MCP args on services create/update; UI Build &
  Resources card; OpenAPI + llms.txt + CLI.md.

Verified live: static build of a real repo → nginx image → deployed;
reserves reach HostConfig (shares=256, MemoryReservation=128Mi);
validation rejects bad specs; builder persists + clears.

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

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

app/frontend/src/lib/api-client.ts

@@ -58,6 +58,11 @@ export type ServiceEntity = {
   domains?: ServiceDomain[];
   maintenanceMode?: boolean;
   basicAuth?: string[];
+  builder?: 'auto' | 'railpack' | 'nixpacks' | 'dockerfile' | 'static';
+  cpuReserve?: string;
+  memoryReserve?: string;
+  staticBuildCmd?: string;
+  staticDir?: string;
   publicUrl?: string;
 };
 
@@ -584,6 +589,11 @@ function normalizeService(service: RawService): ServiceEntity | null {
     domains: service.domains as ServiceDomain[] | undefined,
     maintenanceMode: service.maintenance_mode,
     basicAuth: service.basic_auth as string[] | undefined,
+    builder: service.builder as ServiceEntity['builder'],
+    cpuReserve: service.cpu_reserve,
+    memoryReserve: service.memory_reserve,
+    staticBuildCmd: service.static_build_cmd,
+    staticDir: service.static_dir,
     publicUrl: service.public_url,
   };
 }