feat(observability): restore monitoring coverage, make gaps visible, stream executions

Monitoring coverage was 3 of 89 active entities. Three bugs, each hidden by
discarded errors in checkdefaults:

- writeCheck generated a fresh uuid, inserted the check entity ON CONFLICT
  (slug) DO NOTHING, then wrote a check_defs row referencing it. On any
  re-seed the slug already existed, the entity insert no-oped, and the FK
  violated — aborting the ingest transaction and surfacing as an unrelated
  failure several entities later. Re-seeding has been broken since; prod's
  coverage was frozen at its first successful seed. This is what
  TestSeedIngestIdempotentAndNoDuplicateEdges had been reporting.
- shortSlug truncated to the last 8 chars, so all 21 ingress routes collapsed
  to ".network" and overwrote each other; service:jellyfin collided with
  lxc:jellyfin.
- The ssh-script checker never read the `args` config checkdefaults wrote, so
  process_check.sh always ran without its unit name and returned "unknown".

Coverage is now 75/89. Monitoring is declared per entity type in
seeds/ontology.yaml and resolved through the is-a hierarchy, so a type can say
it warrants nothing (site, lan, mesh, cluster) and never be reported as a gap.
coverageSweep raises an `unmonitored` signal only where a type declares
monitoring it lacks — 8 real gaps, no false positives.

Also:
- entity_types.attribute_schema was never ingested: the seed loader read
  "attribute_schema" but the YAML says "attributes", so all 60 types stored
  JSON null.
- ListExecutions ignored its declared target/action/correlation_id filters and
  paginated on a non-unique target slug, dropping and repeating rows.
- started_at was captured but only written at terminal state, so a running
  execution reported NULL for its whole life. The three MCP auto-run copies
  wrote no timing at all; they are now one autoRun helper.
- SSH output was buffered to completion and discarded entirely on timeout.
  Both sshExec copies now stream through a shared execlog sink into
  execution_logs, and keep partial output when a command is cancelled.
- executions.correlation_id was a random per-execution uuid that correlated
  nothing; it is now the chat session id, which is what lets the chat tail
  live output.
- reversible_low had no auto-run branch despite policy declaring it
  unattended. Since computeCommandRisk never returns it, the class only arises
  when an agent declares it over a read_only command — so gating it penalised
  candor without adding safety.
- backup-target gains a backup-freshness checker (portable find -mmin, since
  the first target is on macOS), resolving its host by walking backs-up-to
  backwards. The pre-deploy pg_dump is now a tracked backup target.

UI: an Executions section on entity detail with live output tailing, and
streamed output under a running `run` call in the chat timeline.

Migrations 022-024. Ops.svelte and context.ts exclude execution.output from
their refetch triggers, which would otherwise fire once a second per command.

Co-Authored-By: Claude <noreply@anthropic.com>

web/vite.config.ts

@@ -32,6 +32,16 @@ function authProxy(target: string, rewrite?: (path: string) => string): ProxyOpt
   }
 }
 
+// Where `npm run dev` proxies to. The SPA is hardwired to same-origin in dev
+// (see the __OIKOS_DEV_TOKEN__ define below), so these targets — not
+// localStorage — decide which backend a dev session actually talks to. They
+// default to the local prod stack, which is what you want day to day; override
+// them to point a dev SPA at a scratch API without touching this file:
+//
+//   OIKOS_API_PROXY=http://127.0.0.1:8199 npm run dev
+const apiTarget = process.env.OIKOS_API_PROXY ?? 'http://localhost:8090'
+const nomosTarget = process.env.OIKOS_NOMOS_PROXY ?? 'http://localhost:8092'
+
 export default defineConfig({
   plugins: [tailwindcss(), svelte()],
   base: '/',
@@ -71,11 +81,11 @@ export default defineConfig({
   },
   server: {
     proxy: {
-      '/api': authProxy('http://localhost:8090'),
+      '/api': authProxy(apiTarget),
       // Production Caddy strips /agent before forwarding to nomos
       // (compose/caddy/Caddyfile.oikos handle_path /agent/*); match that
       // here so dev and prod agree on nomos's actual route paths.
-      '/agent': authProxy('http://localhost:8092', (path) => path.replace(/^\/agent/, ''))
+      '/agent': authProxy(nomosTarget, (path) => path.replace(/^\/agent/, ''))
     }
   },
   test: {