[REV-1714] Use server-authoritative AI credit availability in the client

[warp-agent-staging]

Summary

Supersedes #14352 with its conflicts resolved against current master.

Consumes the server-authoritative User.aiCreditAvailability GraphQL field (warp-server #12935 / #13369) so the client no longer infers overall AI availability from stale request limits, grants, or workspace metadata.

AIRequestUsageModel holds the server decision with last-known-good semantics. Prompt alerts, the buy-credits banner, AI Assistant, Agent Mode, and code review use the shared availability. An OUT_OF_CREDITS denial is refined by usable local API keys or loaded local-chain Bedrock credentials when policy permits; delinquency and spend-limit denials are hard rejections.

Client behavior

• Mirrors AICreditAvailability GraphQL types with forward-compatible unknown enum handling.
• Receives availability through workspace metadata and coalesced targeted refreshes after auth, credential, workspace, add-on credit, and overage changes.
• Resets availability on logout and keeps the last successful decision across transient refresh failures.
• Maps delinquency and enterprise spend-limit reasons to existing presentation states.
• Uses authoritative availability for the buy-credits banner and re-renders it on CreditAvailabilityUpdated.
• Renames the legacy helper to has_base_plan_requests_remaining() and narrows it to pub(crate). Its remaining consumers are intentionally base-quota-specific: anonymous request-limit gates, overage refresh heuristics, default-model-switch presentation, and the pre-fetch fallback.

Server dependency

Requires:

• warp-server#13369 (merged): shared inference-admission and availability semantics.
• warp-server#13719: direct-federation Gemini Enterprise availability and post-model GEAP/Bedrock credential recognition.

The server follow-up must deploy before this client change ships. Without it, a valid direct-federation Gemini Enterprise configuration can be reported as out of credits, or the client can be enabled and then receive an out-of-credits response when submitting.

Conflict resolution

Merged origin/master into the source branch. Six files conflicted, all mechanical "both sides added a field / test" collisions between this change (ai_credit_availability) and master's user-level add-on-credits purchase policy (user_purchase_policy)—both were kept:

• app/src/workspaces/user_workspaces.rs
• app/src/workspaces/gql_convert.rs
• app/src/workspaces/update_manager.rs
• crates/graphql/src/api/queries/get_workspaces_metadata_for_user.rs
• app/src/workspaces/update_manager_tests.rs
• app/src/workspaces/user_workspaces_tests.rs

Master's new gql_user helper was extended with ai_credit_availability, and affected workspace test harnesses register the telemetry and request-usage models required by the combined changes.

Verification

• cargo nextest run -p warp -E 'test(request_usage_model) + test(prompt_alert)' --no-fail-fast — 56 passed.
• cargo nextest run -p warp -E 'test(credit_availability) + test(request_usage_model) + test(prompt_alert) + test(update_manager) + test(user_workspaces)' — 171 passed after the master merge.
• cargo nextest run -p warp_graphql — 7 passed.
• ./script/format
• cargo clippy -p warp --all-targets --tests -- -D warnings
• cargo clippy --workspace --exclude warp_completer --all-targets --tests -- -D warnings

Manual decision-matrix validation

Validated with the client connected to a live local warp-server while forcing only the aiCreditAvailability resolver response. Request middleware and admission logic remained production-identical.

• Warp credits available, no local BYO: no prompt restriction, no buy-credits banner, normal model controls.
• No credits or BYO: buy-credits banner and composer out-of-credits state shown with the expected add-credits CTA.
• OUT_OF_CREDITS + local API key: both restrictions disappear; a real request succeeds through the production admission path.
• OUT_OF_CREDITS + local-chain Bedrock: restrictions remain before aws login; after credentials load, both disappear.
• Server-managed availability (available=true, null credit source): trusted without local credentials.
• DELINQUENT + local key: remains blocked with "Restricted due to payment issue."
• Enterprise spend limit + local key: remains blocked with the spend-limit presentation.

The first live case exposed that the buy-credits banner still used base request counts even though the composer used authoritative availability. This PR now drives both from the same decision and includes focused banner coverage.

Gemini Enterprise end-to-end control

Using the real production resolver and an enterprise direct-federation Gemini configuration:

1. Removed Warp inference credit sources while keeping Gemini configured.
2. Reproduced the out-of-credits availability mismatch.
3. Applied server PR Telugu (and other Indic-script) terminal output renders with wrong cell widths — squeezed/overlapping/torn text #13719; the client restriction disappeared.
4. Reproduced and fixed the downstream request credit guard; the Gemini request succeeded.
5. Restored WARP_PLAN and repeated the request: provider-inference cost remained zero and the local Oz task recorded 0.250051 platform credits (displayed as 0.3), confirming customer-inference billing.

Computer-use screenshots

Originating thread: https://warp-dev.slack.com/archives/C0BDQDW8V5E/p1785680392740989

Conversation: https://staging.warp.dev/conversation/e786e128-f77e-4ff6-9a41-528e9eb60953
Run: https://oz.staging.warp.dev/runs/019fc2e3-2949-72e9-808f-7f6e05af09e9
Plans:

• Client: server-authoritative AI credit availability (REV-1714)

Co-Authored-By: Oz oz-agent@warp.dev

CHANGELOG-IMPROVEMENT: Out-of-credits, delinquency, and spend-limit states across AI surfaces now reflect the server's authoritative credit availability, so they stay accurate as your plan, credits, or API keys change.

This PR was generated with Oz.