feat: add application log ingestion with OpenSearch storage

Agents can now send application log entries in batches via POST /api/v1/data/logs.
Logs are indexed directly into OpenSearch daily indices (logs-{yyyy-MM-dd}) using
the bulk API. Index template defines explicit mappings for full-text search readiness.

New DTOs (LogEntry, LogBatch) added to cameleer3-common in the agent repo.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

cameleer3-server-app/src/main/java/com/cameleer3/server/app/controller/LogIngestionController.java

@@ -0,0 +1,61 @@
+package com.cameleer3.server.app.controller;
+
+import com.cameleer3.common.model.LogBatch;
+import com.cameleer3.server.core.agent.AgentInfo;
+import com.cameleer3.server.core.agent.AgentRegistryService;
+import com.cameleer3.server.core.logging.LogIndexService;
+import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.responses.ApiResponse;
+import io.swagger.v3.oas.annotations.tags.Tag;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.ResponseEntity;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping("/api/v1/data")
+@Tag(name = "Ingestion", description = "Data ingestion endpoints")
+public class LogIngestionController {
+
+    private static final Logger log = LoggerFactory.getLogger(LogIngestionController.class);
+
+    private final LogIndexService logIndexService;
+    private final AgentRegistryService registryService;
+
+    public LogIngestionController(LogIndexService logIndexService,
+                                  AgentRegistryService registryService) {
+        this.logIndexService = logIndexService;
+        this.registryService = registryService;
+    }
+
+    @PostMapping("/logs")
+    @Operation(summary = "Ingest application log entries",
+            description = "Accepts a batch of log entries from an agent. Entries are indexed in OpenSearch.")
+    @ApiResponse(responseCode = "202", description = "Logs accepted for indexing")
+    public ResponseEntity<Void> ingestLogs(@RequestBody LogBatch batch) {
+        String agentId = extractAgentId();
+        String application = resolveApplicationName(agentId);
+
+        if (batch.getEntries() != null && !batch.getEntries().isEmpty()) {
+            log.debug("Received {} log entries from agent={}, app={}", batch.getEntries().size(), agentId, application);
+            logIndexService.indexBatch(agentId, application, batch.getEntries());
+        }
+
+        return ResponseEntity.accepted().build();
+    }
+
+    private String extractAgentId() {
+        Authentication auth = SecurityContextHolder.getContext().getAuthentication();
+        return auth != null ? auth.getName() : "";
+    }
+
+    private String resolveApplicationName(String agentId) {
+        AgentInfo agent = registryService.findById(agentId);
+        return agent != null ? agent.application() : "";
+    }
+}