Add Terraform import functionality to resources

[BCook98]

This commit adds import functionality to five LiteLLM resources using schema.ImportStatePassthroughContext, which passes the resource ID directly to the Read function during import operations.

Resources updated:

• litellm_key: Import using key ID
• litellm_model: Import using model ID
• litellm_mcp_server: Import using server ID
• litellm_team: Import using team ID
• litellm_vector_store: Import using vector store ID

All resources already have proper Read functions that:

• Fetch resources by ID from the API
• Handle 404/not-found cases gracefully
• Populate state with all attributes

Documentation already includes import instructions for all resources.

Usage:
terraform import litellm_key.example
terraform import litellm_model.example
terraform import litellm_mcp_server.example
terraform import litellm_team.example
terraform import litellm_vector_store.example

🤖 Generated with Claude Code

[BCook98]

I've published this as https://registry.terraform.io/providers/BCook98/litellm/0.4.0-alpha.3, if you'd like to test prior to merging.

[BCook98]

This also appears to have changed in the LiteLLM API since this terraform provider was implemented.

With

# (imported from "55de53d4-da3c-430a-bba3-8e0c847d37a8")
~ resource "litellm_team" "<redacted>" {
--
  | blocked                 = false
  | ~ budget_duration         = "24h" -> "30d"
  | id                      = "55de53d4-da3c-430a-bba3-8e0c847d37a8"
  | ~ max_budget              = 0 -> 100
  | + metadata                = {
  | + "environment" = "development"
  | + "managed_by"  = "terraform"
  | + "team"        = "<redacted>"
  | }
  | models                  = [
  | "all-proxy-models",
  | ]
  | organization_id         = null
  | rpm_limit               = 0
  | team_alias              = "<redacted>"
  | team_member_permissions = []
  | tpm_limit               = 0
  | }

Without

# (imported from "55de53d4-da3c-430a-bba3-8e0c847d37a8")
--
  | ~ resource "litellm_team" "<redacted>" {
  | blocked                 = false
  | + budget_duration         = "30d"
  | id                      = "55de53d4-da3c-430a-bba3-8e0c847d37a8"
  | ~ max_budget              = 0 -> 100
  | ~ metadata                = {
  | + "environment" = "development"
  | + "managed_by"  = "terraform"
  | + "team"        = "<redacted>"
  | }
  | ~ models                  = [
  | + "all-proxy-models",
  | ]
  | organization_id         = null
  | rpm_limit               = 0
  | + team_alias              = "<redacted>"
  | team_member_permissions = []
  | tpm_limit               = 0
  | }