feat: single-source cross-app wire contracts in @boocode/contracts (v2.7.13)

Move all hand-synced cross-app wire contracts into one built workspace
package, @boocode/contracts, consumed by server/web/coder/coder-web via
workspace:* + a per-subpath exports map. The ws-frames and provider-config
Zod schemas are schema-first (z.infer); MessageMetadata, ErrorReason,
AgentSessionConfig, the provider snapshot types, and WorktreeRiskReport are
each single-sourced. Deletes the byte-identical copies and their parity
tests, fixes a live AgentSessionConfig drift (coder dead copy removed,
unified to the web required/nullable shape), removes the dead pending_change
WS arms in the fallback SPA, and inverts the build order (contracts builds
first) across root build, Dockerfile, and the coder deploy docs. Reverses
the shared-package decision declined in v2.5.12.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 All notable changes per release tag. Most recent on top, ordered by tag creation date (which matches the git history). Tag names follow `vMAJOR.MINOR.PATCH-slug` — the slug describes what shipped, so the tag name alone is enough to recall the batch.
 
+## v2.7.13-contracts-ssot — 2026-06-02
+
+Creates `@boocode/contracts` (`packages/contracts`), a new workspace package that becomes the single source of truth for every cross-app wire contract — reversing the decision recorded in `v2.5.12-provider-lifecycle-phase4` that declined a shared types package as not worth the Docker/build-order risk at solo scale; a live `AgentSessionConfig` drift that had since appeared between `apps/coder` and `apps/web` justified the investment. Six contracts are now defined exactly once: the `WsFrameSchema` Zod runtime schema, the provider snapshot types (`ProviderSnapshotEntry` and family), the Zod provider-config schemas, `MessageMetadata` + `ErrorReason`, `AgentSessionConfig`, and `WorktreeRiskReport`; both Zod-backed contracts use `z.infer` so validator and type derive from the same definition and cannot drift independently. All four consumers — `apps/server`, `apps/web`, `apps/coder`, and the fallback SPA `apps/coder/web` — import via `workspace:*` through a per-subpath exports map consuming built dist only (no tsconfig project references); the hand-synced copies and their parity tests (`provider-types-parity.test.ts`; the ws-frames byte-parity assertion) are deleted while the KNOWN_FRAME_TYPES drift test and broker fail-closed tests are preserved. Build order is inverted in the root build script, Dockerfile, and coder deploy docs; `apps/coder/web`'s migration also removed dead `pending_change_*` reducer arms (no frame publisher exists for these — pending changes are HTTP-delivered), closing a latent missing-default-arm crash, and reconciled field-type conflicts with the canonical `WsFrame`; zod is pinned to a single version across the workspace. Server 543 / coder 293 / contracts 11 tests passing; human smoke verified on the live stack 2026-06-02.
+
 ## v2.7.11-coder-model-snapshot — 2026-06-02
 
 Hotfix for the coder model-attribution chip vanishing on refresh. The chip showed during a live turn (the `message_complete` frame carries `model`) but disappeared when a BooCoder session was reloaded — only in the coder, not BooChat. Root cause: `CoderPane`'s `useCoderMessages` hydrates from two sources on load — the HTTP `listMessages` fetch (whose SELECT includes `model`, added `v2.7.8`) AND the WS `snapshot` frame — and the WS snapshot's query in `apps/coder/src/routes/ws.ts` had its own column list that omitted `model`. The client's `snapshot` handler `setMessages`-overwrites the HTTP load, so the model-less rows won, and with no later `message_complete` for historical messages the chip stayed gone. Fix is one column: add `model` to the WS snapshot SELECT so both hydration paths agree. The `apps/coder/CLAUDE.md` "update every mapper" note now lists the WS snapshot SELECT explicitly (it was the one place not enumerated). apps/server + apps/coder builds green; deployed via `systemctl restart boocoder` (host service — the earlier `v2.7.10` docker deploy rebuilt only the container, never this route). Fixes the chip shipped in `v2.7.8-ember-coder-tabs-model-chips` / completed in `v2.7.9-mcp-keys-docs-coder-fixes`.