feat(code): cartes liées au code — branches, PRs, commits (issue #1)

app/code_links.py: appariement pur (#n dans titres/corps/messages,
numéro en jeton de branche). Client: list_branches/list_pulls/
list_commits. Badge sur les cartes (board + fragments live),
section Code lié du panneau détail, /api/issues/{o}/{r}/{n}/code.

static/js/board.js

@@ -369,12 +369,40 @@ document.addEventListener('DOMContentLoaded', () => {
             const data = await r.json().catch(() => ({}));
             if (!r.ok || !data.ok) throw new Error(data.error || ('HTTP ' + r.status));
             fillDetail(data.issue, data.comments);
+            loadCodeLinks(repoFull, number);
         } catch (err) {
             document.getElementById('detail-title').textContent = 'Erreur de chargement';
             showToast('❌ Détail indisponible : ' + err.message, true);
         }
     }
 
+
+    async function loadCodeLinks(repoFull, number) {
+        const box = document.getElementById('detail-code');
+        if (!box) return;
+        box.innerHTML = '';
+        const [owner, repo] = repoFull.split('/', 2);
+        try {
+            const r = await fetch(`/api/issues/${owner}/${repo}/${number}/code`);
+            const data = await r.json().catch(() => ({}));
+            if (!r.ok || !data.ok) return;
+            const parts = [];
+            if ((data.branches || []).length) {
+                parts.push('🌿 Branches : ' + data.branches.map(b => `<code>${b}</code>`).join(', '));
+            }
+            for (const pr of data.pulls || []) {
+                const state = pr.merged ? 'fusionnée' : (pr.state === 'open' ? 'ouverte' : 'fermée');
+                parts.push(`🔀 <a href="${pr.html_url}" target="_blank" rel="noopener">PR #${pr.number}</a> ${pr.title} — ${state}`);
+            }
+            for (const c of (data.commits || []).slice(0, 8)) {
+                parts.push(`⑂ <a href="${c.html_url}" target="_blank" rel="noopener"><code>${c.sha}</code></a> ${c.message}${c.date ? ' · ' + c.date : ''}`);
+            }
+            box.innerHTML = parts.length
+                ? '<h3 class="detail-comments-title">🧬 Code lié</h3>' + parts.map(p => `<div class="code-line">${p}</div>`).join('')
+                : '';
+        } catch (err) { /* le code est un bonus, jamais bloquant */ }
+    }
+
     function fillDetail(issue, comments) {
         document.getElementById('detail-title').textContent = issue.title;
         const stateChip = document.getElementById('detail-state');