feat: Public-Flag für Agents + verfügbare Agents/Bots Endpoints erweitert

- AgentRecord: neues IsPublic-Feld mit DB-Migration
- GET /api/agents/available: eigene + public Agents (alle Properties + isOwner)
- GET /api/telegram/bots/available: alle Properties außer Token/Secret + sessionCount
- Agent-Page: Public-Checkbox (andere User können Agent in Sessions verwenden)
- Dashboard: agentMap aus availableAgents gebaut (public Agents fremder User auflösbar)
- Session-Page + Cronjob-Page: Agent-Picker nutzt /available statt /agents
- Agent-Cards: Public- und Fremd-Badges
- Fix: Chat-Button bei Sessions mit public Agent eines anderen Users nicht mehr disabled

wwwroot/js/pages/agent-page.js

@@ -34,6 +34,7 @@ registerPage('agent', {
     const addCommandBtn = document.getElementById('agentAddCommandBtn');
     const skillsSection = document.getElementById('agentSkillsSection');
     const skillList = document.getElementById('agentSkillList');
+    const isPublicEl = document.getElementById('agentIsPublic');
     const more = document.querySelector('.more');
 
     // Avatar Editor initialisieren
@@ -66,6 +67,7 @@ registerPage('agent', {
       useUserInfoEl.checked = agent.useUserInfo !== false;
       useMemoryEl.checked = agent.useMemory !== false;
       webSearchVersionEl.value = agent.webSearchVersion || '';
+      isPublicEl.checked = agent.isPublic || false;
       deleteBtn.hidden = false;
 
       // Custom Commands laden
@@ -112,7 +114,8 @@ registerPage('agent', {
         avatarOffsetX: _agentAvatarEditor.getOffsetX(),
         avatarOffsetY: _agentAvatarEditor.getOffsetY(),
         customCommands: getCommandsFromUI(commandsList),
-        taskInstruction: _agentTaskMde ? _agentTaskMde.value().trim() || null : null
+        taskInstruction: _agentTaskMde ? _agentTaskMde.value().trim() || null : null,
+        isPublic: isPublicEl.checked
       };
 
       if (isNew) {

wwwroot/js/pages/cronjob-page.js

@@ -20,7 +20,7 @@ registerPage('cronjob', {
 
     // Sessions + Agents laden
     const sessions = await apiGetSessions();
-    const agents = await apiGetAgents();
+    const agents = await apiGetAvailableAgents();
     const agentMap = {};
     for (const a of agents) agentMap[a.agentId] = a;
     const sessionMap = {};

wwwroot/js/pages/dashboard.js

@@ -35,11 +35,11 @@ registerPage('dashboard', {
 
     // Telegram-Config parallel pro Session laden (sessions werden gleich geladen)
 
-    const [agents, sessions, cronjobs, shares, telegramBots] = await Promise.all([
-      apiGetAgents(), apiGetSessions(), apiGetCronjobs(), apiListShares(), apiGetTelegramBots()
+    const [agents, availableAgents, sessions, cronjobs, shares, telegramBots] = await Promise.all([
+      apiGetAgents(), apiGetAvailableAgents(), apiGetSessions(), apiGetCronjobs(), apiListShares(), apiGetTelegramBots()
     ]);
     const agentMap = {};
-    for (const a of agents) agentMap[a.agentId] = a;
+    for (const a of availableAgents) agentMap[a.agentId] = a;
 
     // Sessions
     const grid = document.getElementById('sessionCards');

wwwroot/js/pages/session-page.js

@@ -75,7 +75,7 @@ registerPage('session', {
     }
 
     // Agents laden + Skills parallel
-    const agents = await apiGetAgents();
+    const agents = await apiGetAvailableAgents();
     const agentMap = {};
     for (const a of agents) agentMap[a.agentId] = a;