fix: stabilize local model deployment state

[rjckkkkk]

Summary

• Make deploy idempotent for an already-running same-model deployment and surface reused deployments instead of starting duplicates.
• Narrow undeploy matching so ambiguous model-name queries do not remove multiple deployments at once.
• Keep the Agent LLM client/config fresh after deploy/config changes and fold catalog aliases out of model.list so BF16 aliases do not appear as duplicate local models.

Test Plan

• go test ./cmd/aima -run 'Test(DeployApplyReusesExistingSameModelDeploymentByLabel|DeployDeleteRejectsAmbiguousModelNameQuery|DeployDeleteFailsWhenDeploymentStillListedAfterDelete|ListModelsFoldsCatalogAliasesIntoCanonicalModel|BuildFreshAgentStatusPayloadReloadsModelFromDB)$' -count=1
• go test ./internal/knowledge -run TestResolveCatalogModelName -count=1
• go test ./... -count=1
• GOOS=linux GOARCH=amd64 CGO_ENABLED=0 go build -trimpath -o /tmp/aima-pr-final ./cmd/aima

[rjckkkkk]

Follow-up for the desktop-local UI auth issue seen on the 184 server:

• Loopback /ui/ requests now receive a bootstrap API key from the server.
• Non-loopback hosts keep the bootstrap key empty, so LAN UI responses do not include the key.
• Verified on 184: local bootstrap is present, remote-host response has no key, unauthenticated API writes still return 401, authenticated writes return 200.
• Re-packed the desktop bundle at /home/qujing/aima-desktop-build-20260513-ui-auth/aima-linux-amd64-desktop.tar.gz.

[skyguan92]

Re-reviewed after merging current develop and resolving the deploy.delete fallback/exact-name behavior with #57. Local verification passed: targeted deploy.delete regressions and go test ./... on head 1ed098e.