feat(settings): add MCP server configuration

- Add McpSettings component with add/edit/delete server UI
- Support stdio (command + args + env) and sse/http (url + headers) transports
- Array builder for args, key-value builder for env vars and headers
- Pass mcpServers config to SDK query() calls
- Store config as JSON in settings table

1 files changed, 212 insertions, 0 deletions

diff --git a/renderer/src/styles/globals.css b/renderer/src/styles/globals.css
index 0db62c2..6cf3dc7 100644
--- a/renderer/src/styles/globals.css
+++ b/renderer/src/styles/globals.css
@@ -1136,3 +1136,215 @@ html[data-theme="light"] .settings-textarea:focus {
 .cm-scroller::-webkit-scrollbar-thumb:hover {
   background: var(--border);
 }
+
+/* ── MCP Settings ────────────────────────────────────────────── */
+.mcp-server-list {
+  display: flex;
+  flex-direction: column;
+  gap: 8px;
+  margin-top: 16px;
+}
+
+.mcp-empty {
+  color: var(--text-secondary);
+  font-size: 12px;
+  font-style: italic;
+  padding: 12px;
+  text-align: center;
+  border: 1px dashed var(--border);
+  border-radius: 4px;
+}
+
+.mcp-server-card {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  padding: 10px 12px;
+  background: var(--bg-secondary);
+  border: 1px solid var(--border);
+  border-radius: 4px;
+}
+
+.mcp-server-info {
+  display: flex;
+  align-items: center;
+  gap: 10px;
+  min-width: 0;
+  flex: 1;
+}
+
+.mcp-server-name {
+  font-weight: 600;
+  font-size: 13px;
+  color: var(--text-primary);
+}
+
+.mcp-server-type {
+  font-size: 10px;
+  text-transform: uppercase;
+  letter-spacing: 0.05em;
+  padding: 2px 6px;
+  background: var(--bg-tertiary);
+  border-radius: 3px;
+  color: var(--text-secondary);
+}
+
+.mcp-server-detail {
+  font-size: 11px;
+  color: var(--text-secondary);
+  font-family: var(--font-mono, monospace);
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  flex: 1;
+  min-width: 0;
+}
+
+.mcp-server-actions {
+  display: flex;
+  gap: 6px;
+  flex-shrink: 0;
+}
+
+.mcp-error {
+  padding: 8px 12px;
+  background: rgba(239, 68, 68, 0.1);
+  border: 1px solid rgba(239, 68, 68, 0.3);
+  border-radius: 4px;
+  color: #ef4444;
+  font-size: 12px;
+  margin-top: 12px;
+}
+
+.mcp-server-form {
+  margin-top: 16px;
+  padding: 16px;
+  background: var(--bg-secondary);
+  border: 1px solid var(--border);
+  border-radius: 6px;
+}
+
+.mcp-form-title {
+  font-size: 14px;
+  font-weight: 600;
+  color: var(--text-primary);
+  margin-bottom: 16px;
+}
+
+.mcp-form-field {
+  margin-bottom: 14px;
+}
+
+.mcp-form-field label {
+  display: block;
+  font-size: 11px;
+  font-weight: 500;
+  text-transform: uppercase;
+  letter-spacing: 0.05em;
+  color: var(--text-secondary);
+  margin-bottom: 6px;
+}
+
+.mcp-form-field input,
+.mcp-form-field select {
+  width: 100%;
+  padding: 8px 10px;
+  background: var(--bg-primary);
+  border: 1px solid var(--border);
+  border-radius: 4px;
+  color: var(--text-primary);
+  font-size: 13px;
+  font-family: var(--font-mono, monospace);
+  box-sizing: border-box;
+}
+
+.mcp-form-field input:focus,
+.mcp-form-field select:focus {
+  outline: none;
+  border-color: var(--accent);
+}
+
+.mcp-form-field select {
+  cursor: pointer;
+}
+
+.mcp-array-builder,
+.mcp-kv-builder {
+  display: flex;
+  flex-direction: column;
+  gap: 6px;
+}
+
+.mcp-array-row {
+  display: flex;
+  gap: 6px;
+}
+
+.mcp-array-row input {
+  flex: 1;
+}
+
+.mcp-kv-row {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+}
+
+.mcp-kv-row input:first-child {
+  flex: 0 0 35%;
+}
+
+.mcp-kv-row input:nth-child(3) {
+  flex: 1;
+}
+
+.mcp-kv-sep {
+  color: var(--text-secondary);
+  font-family: var(--font-mono, monospace);
+  font-size: 13px;
+}
+
+.btn-icon {
+  width: 28px;
+  height: 28px;
+  padding: 0;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  background: transparent;
+  border: 1px solid var(--border);
+  border-radius: 4px;
+  color: var(--text-secondary);
+  cursor: pointer;
+  font-size: 16px;
+  flex-shrink: 0;
+}
+
+.btn-icon:hover {
+  background: var(--bg-tertiary);
+  color: var(--text-primary);
+}
+
+.btn-small {
+  padding: 4px 8px;
+  font-size: 11px;
+}
+
+.btn-danger {
+  color: #ef4444;
+  border-color: rgba(239, 68, 68, 0.3);
+}
+
+.btn-danger:hover {
+  background: rgba(239, 68, 68, 0.1);
+  color: #ef4444;
+}
+
+.mcp-form-actions {
+  display: flex;
+  justify-content: flex-end;
+  gap: 8px;
+  margin-top: 20px;
+  padding-top: 16px;
+  border-top: 1px solid var(--border);
+}