refactor: Align vocabulary — component → program / deployment

Canonical terms (see docs/registry.md glossary):
- program: any catalog entry (tool/daemon/frontend) — the software
- service / job: how a program is deployed (systemd .service / .timer)
- deployment: umbrella for the unified service+job+program view

Changes:
- core: ServiceSpec/JobSpec component: → program: (component accepted as
  back-compat validation_alias); DeployedComponent → Deployment.
- api: ComponentSummary/Detail → DeploymentSummary/Detail; GET /components
  → /deployments; GatewayRoute.component → program; GatewayInfo
  .component_count → deployment_count; ServiceActionResponse/action keys
  component → program.
- app: matching type renames, /components → /deployments hook, route
  /component/:name → /deployment/:name, GatewayRoute.program.
- docs: component-registry.md → registry.md (+ canonical glossary);
  CLAUDE.md endpoint list refreshed (drop removed /tools, add typed
  program/service/job + config routes).

Tests: core 92, cli 24, api 52 green; app build clean; ruff clean.

cli/src/castle_cli/commands/list_cmd.py

@@ -54,13 +54,13 @@ def _resolve_stack(config: object, name: str) -> str | None:
     # Check services for program ref
     if name in config.services:
         svc = config.services[name]
-        comp_name = svc.component
+        comp_name = svc.program
         if comp_name and comp_name in config.programs:
             return config.programs[comp_name].stack
     # Check jobs for program ref
     if name in config.jobs:
         job = config.jobs[name]
-        comp_name = job.component
+        comp_name = job.program
         if comp_name and comp_name in config.programs:
             return config.programs[comp_name].stack
     # Direct program