feat(aircoding): AirCoding V2 baseline — deterministic multi-agent architecture

Forked from OpenCode v1.17.4 with multi-agent system:
- 5 agents: aircoding, scheduler, worker, architect, reviewer
- Deterministic DAG scheduling engine (coordinator_tick)
- Tool whitelists as hard enforcement
- AirCoding validation plugin
- V1 requirements: C4 docs, ADR, AGENTS.md, debug-log.md
- Design documents in docs/

packages/server/src/errors.ts

@@ -0,0 +1,86 @@
+import { Schema } from "effect"
+
+export class InvalidRequestError extends Schema.TaggedErrorClass<InvalidRequestError>()(
+  "InvalidRequestError",
+  {
+    message: Schema.String,
+    kind: Schema.optional(Schema.String),
+    field: Schema.optional(Schema.String),
+  },
+  { httpApiStatus: 400 },
+) {}
+
+export class UnauthorizedError extends Schema.TaggedErrorClass<UnauthorizedError>()(
+  "UnauthorizedError",
+  { message: Schema.String },
+  { httpApiStatus: 401 },
+) {}
+
+export class ConflictError extends Schema.TaggedErrorClass<ConflictError>()(
+  "ConflictError",
+  {
+    message: Schema.String,
+    resource: Schema.optional(Schema.String),
+  },
+  { httpApiStatus: 409 },
+) {}
+
+export class ServiceUnavailableError extends Schema.TaggedErrorClass<ServiceUnavailableError>()(
+  "ServiceUnavailableError",
+  {
+    message: Schema.String,
+    service: Schema.optional(Schema.String),
+  },
+  { httpApiStatus: 503 },
+) {}
+
+export class UnknownError extends Schema.TaggedErrorClass<UnknownError>()(
+  "UnknownError",
+  {
+    message: Schema.String,
+    ref: Schema.optional(Schema.String),
+  },
+  { httpApiStatus: 500 },
+) {}
+
+export class ProviderNotFoundError extends Schema.TaggedErrorClass<ProviderNotFoundError>()(
+  "ProviderNotFoundError",
+  {
+    providerID: Schema.String,
+    message: Schema.String,
+  },
+  { httpApiStatus: 404 },
+) {}
+
+export class SessionNotFoundError extends Schema.TaggedErrorClass<SessionNotFoundError>()(
+  "SessionNotFoundError",
+  {
+    sessionID: Schema.String,
+    message: Schema.String,
+  },
+  { httpApiStatus: 404 },
+) {}
+
+export class InvalidCursorError extends Schema.TaggedErrorClass<InvalidCursorError>()(
+  "InvalidCursorError",
+  { message: Schema.String },
+  { httpApiStatus: 400 },
+) {}
+
+export class PermissionNotFoundError extends Schema.TaggedErrorClass<PermissionNotFoundError>()(
+  "PermissionNotFoundError",
+  {
+    requestID: Schema.String,
+    message: Schema.String,
+  },
+  { httpApiStatus: 404 },
+) {}
+
+export class QuestionNotFoundError extends Schema.TaggedErrorClass<QuestionNotFoundError>()(
+  "QuestionNotFoundError",
+  {
+    requestID: Schema.String,
+    message: Schema.String,
+  },
+  { httpApiStatus: 404 },
+) {}