feat: implement check-updates, job-backed ingest status, and dedup scan

Replace the four stub endpoints with real implementations, all requiring
an explicit tenant user (Phase B rule):

- /ingest/check-updates: GraphService now records a SHA-256 content_hash
  on every Document node at ingestion time; the endpoint compares those
  stored hashes against current Wiki.js page content in one UNWIND Cypher
  query per tenant and returns changed/new/deleted page lists (entity-stub
  pages excluded, pre-hash-tracking documents flagged stored_hash_missing).
- /ingest/status/{job_id}: backed by the Redis JobManager; jobs are
  tenant-scoped (foreign jobs 404). /ingest/page, /ingest/batch and
  /ingest/all now create job records and return job_id.
- /ingest/repo-status/{repository}: wiki page count vs indexed Document
  nodes under users/{tenant}/{repository} plus tenant job stats.
- /deduplicate/check: tenant-scoped Qdrant similarity scan; chunk pairs
  above ~0.9 cosine from different pages grouped per page pair with best
  score and page references (read-only).

Supporting changes: get_job_manager dependency (+ shutdown close),
scroll_all_points can return vectors, VectorService.find_duplicate_pairs,
src/core/hashing.compute_content_hash. 13 new offline unit tests.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QbFZyDvYksazX6nYQYZ67L

src/core/dependencies.py

@@ -175,6 +175,21 @@ def get_redis_client() -> aioredis.Redis:
     return client
 
 
+@lru_cache
+def get_job_manager() -> "JobManager":
+    """
+    Get Redis-backed JobManager singleton.
+
+    Returns:
+        JobManager for background job tracking (connects lazily)
+    """
+    from src.jobs.job_manager import JobManager
+    settings = get_settings()
+    manager = JobManager(redis_url=settings.redis_url)
+    logger.debug(f"Created JobManager: {settings.redis_url}")
+    return manager
+
+
 @lru_cache
 def get_content_extractor() -> ContentExtractor:
     """
@@ -368,6 +383,9 @@ PaperlessDep = Annotated[PaperlessClient, Depends(get_paperless_client)]
 SettingsClientDep = Annotated[SettingsClient, Depends(get_settings_client)]
 SchedulerDep = Annotated[SchedulerClient, Depends(get_scheduler_client)]
 
+from src.jobs.job_manager import JobManager  # noqa: E402
+JobManagerDep = Annotated[JobManager, Depends(get_job_manager)]
+
 # External API provider dependencies
 WeatherProviderDep = Annotated[OpenMeteoProvider, Depends(get_weather_provider)]
 NewsProviderDep = Annotated[AggregatedNewsProvider, Depends(get_news_provider)]
@@ -527,6 +545,14 @@ async def shutdown_clients():
     except Exception as e:
         logger.error(f"Error closing scheduler client: {e}")
 
+    # Close job manager Redis connection
+    try:
+        job_manager = get_job_manager()
+        await job_manager.close()
+        logger.info("✓ JobManager closed")
+    except Exception as e:
+        logger.error(f"Error closing JobManager: {e}")
+
     logger.info("Service clients shutdown complete")
 
 

src/core/hashing.py

@@ -0,0 +1,26 @@
+"""
+Content hashing helpers.
+
+A single canonical hash implementation is used everywhere page content is
+fingerprinted (Document nodes at ingestion time, /ingest/check-updates
+comparisons) so hashes computed at different times are comparable.
+"""
+
+import hashlib
+
+
+def compute_content_hash(content: str) -> str:
+    """
+    Compute the canonical content hash for wiki page content.
+
+    Args:
+        content: Raw page content (markdown). None-safe: treated as "".
+
+    Returns:
+        Hex-encoded SHA-256 digest of the UTF-8 encoded content.
+
+    Examples:
+        >>> compute_content_hash("hello")
+        '2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824'
+    """
+    return hashlib.sha256((content or "").encode("utf-8")).hexdigest()