fix(models): read a relay's own capacity report and version notation

[pengwei269446668]

Problem

A relay / custom OpenAI-compatible endpoint (e.g. https://sidrune.ai serving deepseek-v4-flash, claude-sonnet-4.5, gemini-3.1-pro) loses the context window its own model list publishes and falls back to the generic 128k / 8192 seed. Older versions (e.g. v0.16.0) resolved these; current main does not.

Root cause: 62cf3c257 fix(models): use models.dev as metadata authority removed the relayChatMetadata fallback in models-dev-catalog.ts, so an unanchored relay id that the catalog does not publish verbatim got nothing. In addition, the service's own capacity report on its model-list row was discarded, and a relay naming a model in the owner's other notation (4.5 vs 4-5) or by the owner's canonical generation id never reached a record.

Fix

1. Read the endpoint's own capacity report (model-discovery.ts, ipc/provider-ipc.ts). A model-list row that states context_window / context_length / inputTokenLimit / contextWindow (and the matching output keys) keeps that value, and the settings row prefers it over both the catalog and any stored value — PiDeck parity: reported > catalog > nothing. An omission is never guessed.
2. Notation aliases (models-dev-catalog.ts). A dotted version name (claude-sonnet-4.5) now reads the owner's dashed published record (claude-sonnet-4-5); each alias is checked as a whole published id, next to the existing single-whitelisted-deployment-label strip (-1m, -test, …).
3. Canonical generation names (models-dev-catalog.ts). A relay naming the owner's canonical_model_id (deepseek-v4.1-flash) is answered by the owner's own live (non-deprecated) record, since the owner publishes that generation only under version aliases.
4. Owner-record fallback for unanchored relays (models-dev-catalog.ts, pi-model-metadata.ts). When no provider is anchored, only the weight owner's records for the family (claude→anthropic, gpt/o1/o3/o4→openai, gemini→google, grok→xai, mimo→xiaomi, glm→zai, deepseek→deepseek, kimi→moonshotai, minimax→minimax) may answer.

Invariants preserved (approved #1047 matching rules):

• Reseller copies never decide a window or a capability.
• The wire id is never rewritten; only whitelisted deployment labels are stripped.
• Variants (-thinking, dated releases) and generations the catalog does not publish stay unmatched.

Verification

• models-dev-catalog.test.mjs + model-discovery.test.mjs: 69/69 pass.
• npx tsc -p tsconfig.json --noEmit: exit 0.
• Full desktop suite vs the same tree at 9fa3abdee: no new failures (the only deltas are pre-existing, flaky, timeout-bound UI/Markdown tests that pass when run alone).
• Probes on the fix: deepseek-v4-flash → deepseek ctx=1000000 out=393216, claude-sonnet-4.5 → anthropic as=claude-sonnet-4-5, deepseek-v4.1-flash → deepseek as=deepseek-flash ctx=1000000, mimo-v2.5-pro-1m → xiaomi, some-private-model → UNMATCHED.

Known pre-existing failures (not touched here)

• provider-endpoint-metadata.test.mjs: on Windows the fixture uses new URL(...).pathname, which yields /E:/… with a leading slash, so readFile fails. Fails on main too.
• model-binding-catalog-source.test.mjs: catalog drift (1048576 vs 1050000).
• macOS notarization / plugin / search tests, unrelated to this change.

🤖 Generated with Claude Code