[modularization] Phase 2: Extract data layer — gitea, weather, bitcoin, loaders

Created modules/data/ with 4 data modules:
- data/gitea.js: Centralized Gitea API (commits, PRs, agent status)
- data/weather.js: Open-Meteo weather data fetch
- data/bitcoin.js: Blockstream block height polling
- data/loaders.js: Static file loaders (portals.json, sovereignty-status.json, SOUL.md)

Updated consumers to use data modules instead of direct fetch():
- panels.js: Uses data/gitea.js for agent status
- heatmap.js: Uses data/gitea.js for commit data
- extras.js: Uses data/gitea.js for timelapse, data/bitcoin.js for block height
- portals.js: Uses data/loaders.js for portals.json
- effects.js: Uses data/loaders.js for sovereignty-status.json
- oath.js: Uses data/loaders.js for SOUL.md
- audio.js: Uses data/loaders.js for SOUL.md

Deduplication wins:
- Gitea token centralized (was hardcoded in 3 files)
- SOUL.md now cached (was fetched 3x independently)
- Nexus commits shared cache (was fetched 2x independently)

Refs #421

modules/data/loaders.js

@@ -0,0 +1,45 @@
+// modules/data/loaders.js — Static file loaders (portals.json, sovereignty-status.json, SOUL.md)
+// Writes to S: sovereigntyScore, sovereigntyLabel
+import { S } from '../state.js';
+
+// --- SOUL.md (cached) ---
+let _soulMdCache = null;
+
+export async function fetchSoulMd() {
+  if (_soulMdCache) return _soulMdCache;
+  try {
+    const res = await fetch('SOUL.md');
+    if (!res.ok) throw new Error('not found');
+    const raw = await res.text();
+    _soulMdCache = raw.split('\n').slice(1).map(l => l.replace(/^#+\s*/, ''));
+    return _soulMdCache;
+  } catch {
+    return ['I am Timmy.', '', 'I am sovereign.', '', 'This Nexus is my home.'];
+  }
+}
+
+// --- portals.json ---
+export async function fetchPortals() {
+  const res = await fetch('./portals.json');
+  if (!res.ok) throw new Error('Portals not found');
+  return await res.json();
+}
+
+// --- sovereignty-status.json ---
+export async function fetchSovereigntyStatus() {
+  try {
+    const res = await fetch('./sovereignty-status.json');
+    if (!res.ok) throw new Error('not found');
+    const data = await res.json();
+    const score = Math.max(0, Math.min(100, typeof data.score === 'number' ? data.score : 85));
+    const label = typeof data.label === 'string' ? data.label : '';
+    const assessmentType = data.assessment_type || 'MANUAL';
+
+    S.sovereigntyScore = score;
+    S.sovereigntyLabel = label;
+
+    return { score, label, assessmentType };
+  } catch {
+    return { score: S.sovereigntyScore, label: S.sovereigntyLabel, assessmentType: 'MANUAL' };
+  }
+}