Add autobot-infrastructure manifests for tts-worker, vnc and docker roles #16436

Add autobot-infrastructure manifests for tts-worker, vnc and docker

Found while implementing #16025 (deriving role_registry.DEFAULT_ROLES from
autobot-infrastructure/*/manifest.yml): three roles in
role_registry.DEFAULT_ROLES have no manifest at all under
autobot-infrastructure/:

Every other role in DEFAULT_ROLES maps to a manifest directly, or via the
ManifestService.slm_roles narrowing/fan-out mechanism #16025 added (e.g.
autobot-database's services back redis/postgres/chromadb). These
three fall through to role_manifest_shape.apply_manifest_shape's
"no manifest" branch and stay fully hand-declared -- not a bug, but not the
single source of truth the rest of the fleet now has either.

Acceptance criteria

• autobot-infrastructure/autobot-tts-worker/manifest.yml, validated
  against models/manifest.py's RoleManifest schema, values matching
  the current role_registry.py entry (systemd unit, port, health check)
• autobot-infrastructure/autobot-vnc/manifest.yml, same
• autobot-infrastructure/autobot-docker/manifest.yml, or a decision
  recorded that docker (no systemd unit, no deploy source) does not need
  one and should stay registry-only
• Once added, role_manifest_shape.find_role_manifest resolves all three
  (a direct match, since their registry names already have no
  autobot-<role> mismatch to alias around)

Refs #16025.