feat: add GitHub repository synchronization functionality with document extraction pipeline and update security policy to permit GitHub API access.

src/lib/giteaService.js

@@ -0,0 +1,76 @@
+/**
+ * GitHub API Service
+ * Fetches files from a public GitHub repository directly from the browser.
+ * No proxy or token required for public repos.
+ */
+
+const GITHUB_API  = 'https://api.github.com';
+const GITHUB_RAW  = 'https://raw.githubusercontent.com';
+
+/**
+ * List markdown/text files in a GitHub repository folder.
+ * @param {string} owner  - e.g. "respellion"
+ * @param {string} repo   - e.g. "employee-handbook"
+ * @param {string} folder - e.g. "docs" or "" for root
+ * @param {string} branch - e.g. "main"
+ * @returns {Promise<Array<{name, sha, path}>>}
+ */
+export async function getRepoFolder(owner, repo, folder = '', branch = 'main') {
+  const path = folder ? folder.replace(/^\/|\/$/g, '') : '';
+  const url  = `${GITHUB_API}/repos/${owner}/${repo}/contents/${path}?ref=${branch}`;
+
+  const res = await fetch(url, {
+    headers: { Accept: 'application/vnd.github+json' },
+  });
+
+  if (!res.ok) {
+    const err = await res.json().catch(() => ({}));
+    throw new Error(`GitHub API ${res.status}: ${err.message || 'Could not list folder'}`);
+  }
+
+  const items = await res.json();
+  // Return only files (.md / .txt), not sub-directories
+  return items.filter(
+    item => item.type === 'file' && (item.name.endsWith('.md') || item.name.endsWith('.txt'))
+  );
+}
+
+/**
+ * Fetch the raw text content of a file.
+ * Uses raw.githubusercontent.com — no rate limits for public content.
+ * @param {string} owner
+ * @param {string} repo
+ * @param {string} path   - e.g. "docs/ROLES.md"
+ * @param {string} branch
+ * @returns {Promise<string>}
+ */
+export async function getFileContent(owner, repo, path, branch = 'main') {
+  const url = `${GITHUB_RAW}/${owner}/${repo}/${branch}/${path}`;
+  const res = await fetch(url);
+
+  if (!res.ok) {
+    throw new Error(`Could not fetch "${path}" from GitHub (${res.status})`);
+  }
+
+  return res.text();
+}
+
+/**
+ * Parse a GitHub tree URL into its parts.
+ * e.g. "https://github.com/respellion/employee-handbook/tree/main/docs"
+ * → { owner: 'respellion', repo: 'employee-handbook', branch: 'main', folder: 'docs' }
+ */
+export function parseGitHubUrl(url) {
+  try {
+    const match = url.match(/github\.com\/([^/]+)\/([^/]+)(?:\/tree\/([^/]+)(?:\/(.+))?)?/);
+    if (!match) return null;
+    return {
+      owner:  match[1],
+      repo:   match[2],
+      branch: match[3] || 'main',
+      folder: match[4] || '',
+    };
+  } catch {
+    return null;
+  }
+}