Add tracker description enrichment worker

Tracker descriptions were only filled on the agent-identification path,
so patterns resolved by domain, sibling, or fallback stayed without one,
and empty mapping upserts could clobber a researched description on the
shared catalog row.

Move description ownership to a dedicated, global common-pattern
enrichment worker. New catalog rows are queued on insert; the worker
researches a compliance-grade description with web search, records it on
the common pattern, and fans it out to every linked tracker pattern. The
mapping worker no longer generates descriptions and only propagates an
already-enriched one at link time.

Rename TrackerMappingConfig to TrackerAgentsConfig since the mapping and
enrichment agents now share it.

Signed-off-by: Émile Ré <emile@probo.com>

pkg/cookiebanner/tracker_mapping_agent.go

@@ -26,7 +26,6 @@ import (
 	"go.probo.inc/probo/pkg/agent"
 	"go.probo.inc/probo/pkg/agent/tools/search"
 	"go.probo.inc/probo/pkg/coredata"
-	"go.probo.inc/probo/pkg/llm"
 )
 
 const (
@@ -44,21 +43,11 @@ var trackerIdentificationPrompt string
 type TrackerMappingAgentResult struct {
 	ThirdPartyName string                      `json:"third_party_name" jsonschema:"Name of the company or service that sets this tracker (e.g. 'Google Analytics', 'Meta Pixel'). Empty string if truly unknown."`
 	Category       coredata.ThirdPartyCategory `json:"category" jsonschema:"Third party category"`
-	Description    string                      `json:"description" jsonschema:"What this tracker does in one sentence"`
 	Confidence     float64                     `json:"confidence" jsonschema:"Confidence level from 0.0 to 1.0. Set below 0.5 if unsure."`
 }
 
-// TrackerMappingConfig configures the tracker-mapping agent (catalog
-// identification). The agent uses DB-backed search tools and may also
-// use Firecrawl for web search when an API key is supplied.
-type TrackerMappingConfig struct {
-	LLMClient       *llm.Client
-	Model           string
-	FirecrawlAPIKey string
-}
-
 func buildTrackerMappingAgent(
-	cfg TrackerMappingConfig,
+	cfg TrackerAgentsConfig,
 	pgClient *pg.Client,
 	logger *log.Logger,
 ) *agent.Agent {