feat: 新增「部署客户端」日志采集器模块

三种采集器（host-promtail / k8s-daemonset / k8s-fluentbit-sidecar），每种关联已部署 Loki：
- host-promtail：SSH 安装 Promtail（复用 deployBinary）
- k8s-daemonset：helm 安装 Promtail DaemonSet（复用 deployHelm）
- k8s-fluentbit-sidecar：kubectl patch 注入 Fluent Bit sidecar

含 Collector 数据模型、三个部署器、配置模板、CRUD API、前端页面。
附带 UI 优化：ErrorBoundary、部署卡片浏览器访问按钮、菜单名称调整。

Co-Authored-By: Claude <noreply@anthropic.com>

backend/services/collector_templates.go

@@ -0,0 +1,183 @@
+package services
+
+import (
+	"fmt"
+	"strings"
+)
+
+// PromtailConfig 主机 Promtail 配置（推送至 lokiEndpoint，采集 logPath）
+func PromtailConfig(lokiEndpoint, logPath string) string {
+	return fmt.Sprintf(`server:
+  http_listen_port: 9080
+  grpc_listen_port: 0
+  log_level: info
+
+positions:
+  filename: /tmp/positions.yaml
+
+clients:
+  - url: %s/loki/api/v1/push
+
+scrape_configs:
+  - job_name: app
+    static_configs:
+      - targets: [localhost]
+        labels:
+          job: app
+          host: ${HOSTNAME}
+          __path__: %s
+`, lokiEndpoint, logPath)
+}
+
+// PromtailHelmValues DaemonSet 模式 Promtail Helm values
+func PromtailHelmValues(lokiEndpoint string) string {
+	return fmt.Sprintf(`config:
+  clients:
+    - url: %s/loki/api/v1/push
+
+daemonset:
+  enabled: true
+
+serviceAccount:
+  create: true
+
+resources:
+  limits:
+    cpu: 200m
+    memory: 128Mi
+  requests:
+    cpu: 100m
+    memory: 64Mi
+
+extraVolumes:
+  - name: varlog
+    hostPath:
+      path: /var/log
+  - name: varlibdockercontainers
+    hostPath:
+      path: /var/lib/docker/containers
+
+extraVolumeMounts:
+  - name: varlog
+    mountPath: /var/log
+    readOnly: true
+  - name: varlibdockercontainers
+    mountPath: /var/lib/docker/containers
+    readOnly: true
+`, lokiEndpoint)
+}
+
+// FluentbitConfig Sidecar 模式 Fluent Bit 配置（采集 logPath，推送至 lokiHost:lokiPort）
+func FluentbitConfig(lokiHost, lokiPort, logPath, app, namespace string) string {
+	return fmt.Sprintf(`[SERVICE]
+    Flush          5
+    Log_Level      info
+    HTTP_Server    On
+    HTTP_Listen    0.0.0.0
+    HTTP_Port      2020
+
+[INPUT]
+    Name              tail
+    Path              %s
+    Tag               app.%s
+    Refresh_Interval  5
+    Mem_Buf_Limit     5MB
+    Skip_Long_Lines   On
+    Read_from_Head    True
+    DB                /tmp/flb.db
+
+[FILTER]
+    Name    modify
+    Match   app.*
+    Add     namespace %s
+    Add     app %s
+
+[OUTPUT]
+    Name                loki
+    Match               *
+    Host                %s
+    Port                %s
+    Labels              job=fluent-bit, app=%s, namespace=%s
+`, logPath, app, namespace, app, lokiHost, lokiPort, app, namespace)
+}
+
+// FluentbitConfigMapYAML 包装 fluent-bit.conf 为 ConfigMap YAML（部署到 namespace）
+func FluentbitConfigMapYAML(conf, namespace string) string {
+	return fmt.Sprintf(`apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: fluent-bit-config
+  namespace: %s
+data:
+  fluent-bit.conf: |
+%s
+`, namespace, indentBlock(conf, "    "))
+}
+
+// SidecarPatchYAML strategic merge patch：为 Deployment 注入 Fluent Bit sidecar 容器
+const SidecarPatchYAML = `spec:
+  template:
+    spec:
+      volumes:
+      - name: app-logs
+        emptyDir: {}
+      - name: fluent-bit-config
+        configMap:
+          name: fluent-bit-config
+      containers:
+      - name: fluent-bit
+        image: cr.fluentbit.io/fluent/fluent-bit:3.1.1
+        imagePullPolicy: IfNotPresent
+        volumeMounts:
+        - name: app-logs
+          mountPath: /var/log/app
+          readOnly: true
+        - name: fluent-bit-config
+          mountPath: /fluent-bit/etc/
+        resources:
+          limits:
+            cpu: 200m
+            memory: 256Mi
+          requests:
+            cpu: 100m
+            memory: 128Mi
+`
+
+// SidecarRemovePatchYAML strategic merge patch：从 Deployment 移除 Fluent Bit sidecar（卸载）
+const SidecarRemovePatchYAML = `spec:
+  template:
+    spec:
+      containers:
+      - name: fluent-bit
+        $patch: delete
+      volumes:
+      - name: app-logs
+        $patch: delete
+      - name: fluent-bit-config
+        $patch: delete
+`
+
+// indentBlock 给每行加前缀（ConfigMap 嵌入配置需缩进）
+func indentBlock(s, pad string) string {
+	lines := strings.Split(s, "\n")
+	for i, l := range lines {
+		if l != "" {
+			lines[i] = pad + l
+		}
+	}
+	return strings.Join(lines, "\n")
+}
+
+// parseLokiURL 从 http://host:port 提取 host 与 port（Fluent Bit OUTPUT 需要）
+func parseLokiURL(endpoint string) (host, port string) {
+	u := strings.TrimSpace(endpoint)
+	u = strings.TrimPrefix(u, "http://")
+	u = strings.TrimPrefix(u, "https://")
+	if i := strings.Index(u, "/"); i >= 0 {
+		u = u[:i]
+	}
+	if i := strings.LastIndex(u, ":"); i >= 0 {
+		return u[:i], u[i+1:]
+	}
+	return u, "3100"
+}