feat(core): gitea read client behind an injected fetch (#1)

createGiteaClient(config, fetchImpl).getIssue(index) fetches one issue
and normalizes raw gitea JSON to a typed GiteaIssue with scheduler
facts precomputed via extractLabelFacts. Network is an injected
FetchLike (core has no DOM lib; global fetch is structurally
assignable), so it unit-tests against a stub — no live calls in the
suite. Non-2xx responses throw GiteaApiError carrying status + body.

Closes P1-1. Verified end-to-end against the live repo's issue #9.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/core/src/gitea/client.ts

@@ -0,0 +1,97 @@
+/**
+ * Gitea read client. One method for now — `getIssue` — proving the vertical
+ * slice end to end: config + injected fetch → typed, normalized `GiteaIssue`
+ * with scheduler facts precomputed. Later reconcile work (P1-4) layers list
+ * reads on the same `request` seam.
+ */
+
+import { extractLabelFacts } from '../labels/label-schema.js'
+import {
+  GiteaApiError,
+  type FetchLike,
+  type GiteaConfig,
+  type GiteaIssue,
+  type GiteaMilestoneRef,
+} from './types.js'
+
+/** The subset of gitea's raw issue JSON we read. */
+interface RawLabel {
+  name: string
+}
+interface RawMilestone {
+  id: number
+  title: string
+  due_on: string | null
+}
+interface RawUser {
+  login: string
+}
+interface RawIssue {
+  number: number
+  title: string
+  body: string | null
+  state: string
+  labels: RawLabel[] | null
+  milestone: RawMilestone | null
+  assignee: RawUser | null
+  assignees: RawUser[] | null
+  created_at: string
+  updated_at: string
+  closed_at: string | null
+  html_url: string
+}
+
+export interface GiteaClient {
+  /** Fetch one issue by its per-repo index, normalized. */
+  getIssue(index: number): Promise<GiteaIssue>
+}
+
+/** Map raw gitea issue JSON to the normalized domain shape. Pure. */
+export function normalizeIssue(raw: RawIssue): GiteaIssue {
+  const labels = (raw.labels ?? []).map((l) => l.name)
+  const milestone: GiteaMilestoneRef | null = raw.milestone
+    ? { id: raw.milestone.id, title: raw.milestone.title, dueOn: raw.milestone.due_on }
+    : null
+  const assignees = (raw.assignees ?? []).map((u) => u.login)
+
+  return {
+    number: raw.number,
+    title: raw.title,
+    body: raw.body ?? '',
+    state: raw.state === 'closed' ? 'closed' : 'open',
+    labels,
+    facts: extractLabelFacts(labels),
+    milestone,
+    assignee: raw.assignee?.login ?? null,
+    assignees,
+    createdAt: raw.created_at,
+    updatedAt: raw.updated_at,
+    closedAt: raw.closed_at,
+    url: raw.html_url,
+  }
+}
+
+export function createGiteaClient(config: GiteaConfig, fetchImpl: FetchLike): GiteaClient {
+  const apiBase = `${config.baseUrl.replace(/\/+$/, '')}/api/v1`
+  const repoBase = `${apiBase}/repos/${config.owner}/${config.repo}`
+
+  async function request(path: string): Promise<unknown> {
+    const res = await fetchImpl(`${repoBase}${path}`, {
+      headers: {
+        Authorization: `token ${config.token}`,
+        Accept: 'application/json',
+      },
+    })
+    if (!res.ok) {
+      const body = await res.text().catch(() => '')
+      throw new GiteaApiError(res.status, `GET ${path} failed (${res.status})`, body)
+    }
+    return res.json()
+  }
+
+  return {
+    async getIssue(index) {
+      return normalizeIssue((await request(`/issues/${index}`)) as RawIssue)
+    },
+  }
+}