[feature]: Add Alibaba Token Plan (alibaba-token-plan) quota provider support

[lucasrochaqw]

Pre-flight checks

• I searched existing issues and did not find a duplicate request.
• I reviewed current behavior on the production released OpenCode version.

OpenCode version reviewed

1.18.30 (opencode-quota 4.8.2 installed; verified the same gaps still exist in 4.9.0)

Problem statement

The alibaba-token-plan provider (registered on models.dev as "Alibaba Token Plan", e.g. alibaba-token-plan/qwen3.8-max) is never detected by opencode-quota. With enabledProviders: "auto" and a valid auth.json entry:

{ "alibaba-token-plan": { "type": "api", "key": "..." } }

the provider does not appear in /quota, the quota_status tool, the TUI sidebar, or ~/.cache/opencode/quota-provider-state/. Only alibaba-coding-plan / alibaba are recognized.

Root-cause pointers in dist/ (same in 4.8.2 and 4.9.0):

• lib/alibaba-auth.js — ALIBABA_AUTH_KEYS and ALIBABA_PROVIDER_KEYS are ["alibaba-coding-plan", "alibaba"]; allowed env vars are only ALIBABA_CODING_PLAN_API_KEY / ALIBABA_API_KEY; isAlibabaModelId() only matches alibaba/ and alibaba-cn/ prefixes.
• lib/qwen-local-quota.js — local usage counting only scans messages with providerIds: ["alibaba-coding-plan", "alibaba"], so traffic on alibaba-token-plan/* models is never attributed.
• lib/provider-metadata.js — alibaba-coding-plan entry has runtimeIds: ["alibaba-coding-plan"], synonyms: ["alibaba"]; nothing maps alibaba-token-plan.

Provider facts (from models.dev / Alibaba docs):

• API base: https://token-plan.ap-southeast-1.maas.aliyuncs.com/compatible-mode/v1 (OpenAI-compatible)
• Env var: ALIBABA_TOKEN_PLAN_API_KEY
• Docs: https://www.alibabacloud.com/help/en/model-studio/token-plan-overview
• models.dev also lists a CN variant alibaba-token-plan-cn (similar to minimax-china-coding-plan handled in [bug]: MiniMax Token Plan (CN) does not display quota #232).

Note: the Token Plan quota is a token-based allowance (per model family / window), not the Coding Plan's request-count windows (lite/pro tiers, 5h/weekly/monthly request caps), so the existing Coding Plan local-estimation limits would not be accurate even if the provider id were simply aliased.

Proposed change

Recognize alibaba-token-plan (and ideally alibaba-token-plan-cn) as a first-class quota provider:

1. Add it to the Alibaba auth/provider key lists (or a dedicated alibaba-token-plan-auth.js), including ALIBABA_TOKEN_PLAN_API_KEY as an allowed env var.
2. Register it in provider-metadata.js (runtimeIds, label "Alibaba Token Plan").
3. Count local usage for messages whose providerID is alibaba-token-plan / model IDs prefixed alibaba-token-plan/ (extend qwen-local-quota.js providerIds and isAlibabaModelId()).
4. Track the Token Plan's token-based windows per its docs rather than the Coding Plan request tiers. If Alibaba exposes no quota/usage endpoint for the Token Plan, a local token-based estimation (analogous to the Coding Plan's local estimation, but summing tokens against the plan's token allowance) would already be very useful.

Alternatives considered

• Aliasing alibaba-token-plan into the existing alibaba-coding-plan auth keys locally: detection would trigger, but usage attribution still misses (providerIds filter and isAlibabaModelId() prefix), and the displayed limits would be the Coding Plan lite/pro request windows, i.e. wrong numbers for a Token Plan subscription.
• Waiting for a generic "all models.dev providers" solution ([feature]: Support all providers from models.dev instead of a hardcoded allowlist #101): closed as stale; a targeted addition matches the precedent of [bug]: MiniMax Token Plan (CN) does not display quota #232 (MiniMax Token Plan CN).

Acceptance criteria

• An auth.json entry alibaba-token-plan: { type: "api", key: ... } (or ALIBABA_TOKEN_PLAN_API_KEY) is detected with enabledProviders: "auto".
• Usage from alibaba-token-plan/* models is attributed and shown in /quota, quota_status, and the TUI sidebar.
• Reported windows/limits reflect the Token Plan's token-based allowance (or are clearly labeled as local estimates), not the Coding Plan request tiers.
• alibaba-token-plan-cn is handled or explicitly documented as out of scope.