Add overdue invoices check (#31290)

- Rename current_user_account_too_young to account_too_young for
consistency
- Add has_overdue_invoices field to track billing status
- Block edit predictions when user has overdue invoices
- Add overdue invoice warning to inline completion menu

Release Notes:

- N/A

---------

Co-authored-by: Marshall Bowers <git@maxdeviant.com>

crates/collab/src/llm/token.rs

@@ -1,5 +1,5 @@
 use crate::db::billing_subscription::SubscriptionKind;
-use crate::db::{billing_subscription, user};
+use crate::db::{billing_customer, billing_subscription, user};
 use crate::llm::AGENT_EXTENDED_TRIAL_FEATURE_FLAG;
 use crate::{Config, db::billing_preference};
 use anyhow::{Context as _, Result};
@@ -32,6 +32,8 @@ pub struct LlmTokenClaims {
     pub enable_model_request_overages: bool,
     pub model_request_overages_spend_limit_in_cents: u32,
     pub can_use_web_search_tool: bool,
+    #[serde(default)]
+    pub has_overdue_invoices: bool,
 }
 
 const LLM_TOKEN_LIFETIME: Duration = Duration::from_secs(60 * 60);
@@ -40,6 +42,7 @@ impl LlmTokenClaims {
     pub fn create(
         user: &user::Model,
         is_staff: bool,
+        billing_customer: billing_customer::Model,
         billing_preferences: Option<billing_preference::Model>,
         feature_flags: &Vec<String>,
         subscription: billing_subscription::Model,
@@ -99,6 +102,7 @@ impl LlmTokenClaims {
                 .map_or(0, |preferences| {
                     preferences.model_request_overages_spend_limit_in_cents as u32
                 }),
+            has_overdue_invoices: billing_customer.has_overdue_invoices,
         };
 
         Ok(jsonwebtoken::encode(