feat(nodes): SSH bootstrap + housekeeping — install script, bundled binaries, auto-prune (#50)

* feat(nodes): SSH bootstrap + housekeeping — install script, bundled binaries, auto-prune

- `containr nodes add <user@host>` mints an enroll token, SSHes once,
  runs the install script remotely; --print emits the one-liner
- Public /api/agents/install.sh + /api/agents/download/{platform};
  agent binaries built into the image under /agents
- Agent-side `prune` (bounded docker system prune, volumes opt-in)
  and `system_df` commands
- node_agents.auto_prune + health sweep enqueues daily prune;
  offline/online transitions notify admins
- CLI nodes update/prune/commands + MCP tools (prune confirm-gated)
- Usage page: install one-liner, per-node Prune + auto toggle

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* feat(nodes): node detail page — telemetry, containers, commands, controls

/nodes/:id (admin): cpu/mem sparklines from heartbeat history
(1h/24h/7d), containers on node, command history, inline rename,
auto-prune toggle, prune-now with volume opt-in, remove. Agent rows
on the Usage page link into it.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* feat(nodes): mesh awareness + node detail page

- agent reports tailscale/netbird/zerotier/wireguard interface IPs at
  register (authoritative — absent interfaces clear stored state)
- backend stores under node_agents.metadata.mesh, merged on re-register
- node detail page shows mesh addresses under the primary IP

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

---------

Co-authored-by: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

app/backend/internal/api/notification_producers.go

@@ -7,6 +7,7 @@ package api
 
 import (
 	"containr/internal/database"
+	"containr/internal/database/sqlcdb"
 	"context"
 	"encoding/json"
 	"fmt"
@@ -61,26 +62,28 @@ func StartAgentHealthSweep(ctx context.Context, db *database.DB) {
 	}()
 }
 
+type agentHealthRow struct {
+	id        string
+	name      string
+	status    string
+	stale     bool
+	autoPrune bool
+}
+
 func reconcileAgentHealth(db *database.DB, staleAfter time.Duration) {
 	cutoff := time.Now().Add(-staleAfter)
-	type agentRow struct {
-		id     string
-		name   string
-		status string
-		stale  bool
-	}
-	var agents []agentRow
+	var agents []agentHealthRow
 	rows, err := db.Query(
 		`SELECT id, COALESCE(name, hostname, id::text), COALESCE(status, ''),
-		        COALESCE(last_heartbeat < $1, TRUE)
+		        COALESCE(last_heartbeat < $1, TRUE), auto_prune
 		 FROM node_agents`, cutoff)
 	if err != nil {
 		log.Printf("containr: agent health sweep: %v", err)
 		return
 	}
 	for rows.Next() {
-		var a agentRow
-		if err := rows.Scan(&a.id, &a.name, &a.status, &a.stale); err == nil {
+		var a agentHealthRow
+		if err := rows.Scan(&a.id, &a.name, &a.status, &a.stale, &a.autoPrune); err == nil {
 			agents = append(agents, a)
 		}
 	}
@@ -104,6 +107,32 @@ func reconcileAgentHealth(db *database.DB, staleAfter time.Duration) {
 				fmt.Sprintf("Agent %s resumed heartbeating.", a.name), "agent", a.id)
 		}
 	}
+
+	scheduleAutoPrune(db, agents)
+}
+
+// scheduleAutoPrune enqueues a `prune` command once per day for agents
+// with auto_prune enabled. Disk pressure is the most common small-VPS
+// failure — this is the dflow setServerAutoCleanup analog.
+func scheduleAutoPrune(db *database.DB, agents []agentHealthRow) {
+	q := sqlcdb.New(db.DB)
+	for _, a := range agents {
+		if !a.autoPrune || a.stale {
+			continue
+		}
+		last, err := q.GetLastAgentCommandByType(context.Background(),
+			sqlcdb.GetLastAgentCommandByTypeParams{NodeAgentID: a.id, Type: "prune"})
+		if err == nil && last.CreatedAt.Valid && time.Since(last.CreatedAt.Time) < 24*time.Hour {
+			continue
+		}
+		if _, err := q.CreateCommand(context.Background(), sqlcdb.CreateCommandParams{
+			ID:          uuid.New().String(),
+			Type:        "prune",
+			NodeAgentID: a.id,
+		}); err != nil {
+			log.Printf("containr: auto-prune enqueue failed for agent %s: %v", a.id, err)
+		}
+	}
 }
 
 // StartUpgradeCheck polls GitHub for the latest release once a day and