fix: display the selected wire provider as JetBrains Air Gateway

[serjic]

Summary

Addresses IJAI-2956.

• Classify the selected agent-owned provider ID returned by getAgentConfiguredModelProvider() as a gateway when it equals wire after trimming, case-insensitively.
• Emit kind: gateway and the exact label JetBrains Air Gateway, with no detail or invented account identity. Do not fetch or inspect the provider's friendly name, URL, backend, or route.
• Preserve effective configuration/launch-override precedence and the separation between authentication identity and client-owned ACP providers/set; an unused wire provider does not affect auth status.
• Use the same classification for the initial status and subsequent updates; retain existing behavior for other providers.
• Add regression coverage for case/whitespace, active selection and overrides, friendly-name negatives, client-owned providers, exact payloads, and source switching; update docs/air-extensions.md.

This is an agreed weak display heuristic, not proof that the endpoint is a Central deployment or that the user has any particular entitlement. A different selected provider ID does not match merely because its friendly name contains wire.

Sanitized auth status

{
  "kind": "gateway",
  "label": "JetBrains Air Gateway"
}

No keys, headers, private routes, technical wire detail, or invented account information is sent.

Verification

Based on fresh upstream main at ca1d971, rechecked immediately before publication. Changes and rebuilt dist are available in the main local clone; the user confirmed the local adapters work.

npm run typecheck
npm run build
npm test

• Typecheck (including examples) and build passed.
• Full test suite: 1218 passed, 33 existing skipped across 76 passed test files and 6 skipped opt-in e2e files.
• Auth-status coverage: 33 tests passed in the targeted run and the full suite.
• No new skip flags or disabled tests were used.

Scope

No AIR UI, provisioning, personal configuration migration, effort/mode changes, or new ACP protocol. Plan files and personal configurations are not committed.

[EugeneTheDev]

This is the only place in the code that explains why a provider ID of wire is shown with JetBrains branding, and right now it explains nothing. Could we pull "wire" and the label into named constants next to DEFAULT_GATEWAY_LABEL, and add a short doc comment like the ones on the neighbouring functions? It should say this is a display-only heuristic on the agent-owned provider ID (see docs/air-extensions.md). Otherwise the next reader has to guess whether matching the bare ID is deliberate.

[EugeneTheDev]

This string is shown to users, and elsewhere (docs, commit history) the product is written AIR, not Air. Was JetBrains Air Gateway checked with the client/product side?