[Loongphy]

WIP / draft — stacked on #159 (base is #159's head branch; this diff contains only the maintainer-review implementation). Will be retargeted to main after #159 merges.

What

Implements the four changes requested in the #159 review:

1. NEXT RESET column removed — its value is always one of the two reset timestamps already embedded in the 5H/WEEKLY cells (58% (14:20 on 22 Oct)); the derived next_reset_at field is removed with it (registry, JSON output, and view layers).
2. ACCESS EXP LOCAL → ACCESS EXPIRE — and the LOCAL suffix pattern is dropped: credit expiry now renders in local time, so every timestamp in the table shares one timezone (the previous per-credit columns pinned the backend timezone).
3. Per-credit columns (C1 EXP, C2 EXP, …) removed — replaced by the enriched RESET CREDITS cell: N (exp MMM-DD) — the persisted count plus the earliest available-card expiry in local form. The old columns were rigid 23-char, grew unbounded with credits.len, showed expiry without card identity, and mixed UTC into the table.
4. schema_version stays 4 — the new fields (access_token_expires_at, last_usage.reset_credit) are optional additive data: older binaries ignore unknown keys, and the data self-heals on the next --api refresh. The v4→v5 migration is dropped.

Persisted credit record

"reset_credit": [
  { "id": "credit-1", "status": "available", "expires_at": "2026-11-01T00:00:00Z",
    "title": "Full reset (Weekly + 5 hr)" },
  { "id": "credit-2", "status": "available", "expires_at": null, "title": null }
]

• Kept: id (upstream opaque identity), status (upstream keeps redeemed rows in the list — RateLimitResetCreditStatus: available/redeeming/redeemed — and rendering filters to available like upstream's picker), expires_at, title (the only human-readable identity).
• Dropped: wrapper available_count (duplicates reset_credits on disk), total_earned_count (upstream drops it too), reset_type / granted_at / description (nothing renders or acts on them).
• Rendering filters to status == available exactly like upstream's picker.

Renames

• auth_expires_at → access_token_expires_at across the registry record, persisted JSON key, fetch layer, view layer, and JSON output — it is specifically the access token's JWT exp, and matches the registry's _at seconds convention (created_at, last_used_at, last_usage_at, resets_at).

Docs

• schema-migration.md stays at the schema 4 policy (v5 history entry removed).
• docs/commands/list.md and docs/json-api.md updated: ACCESS EXPIRE / RESET CREDITS columns, slim reset_credit shape, no next_reset_at, all-local time rendering.

Scope

• No changes to feat: expose credential expiry and reset credits in list output #159's data-flow design: the details fetch, usage parsing, and JSON output remain; only the persisted shape, table columns, and naming change per the review.

Validation

• zig build -Doptimize=ReleaseFast clean; full zig build test exit 0
• pty run of list --live --skip-api: the live table shows ACCESS EXPIRE / RESET CREDITS columns, no NEXT RESET, no per-credit columns, no UTC strings; plain list output is byte-identical to main
• Registry migration verified: v4 files with the new fields load and stay at schema 4