Give each tracker agent its own config

The tracker-mapping, common-pattern enrichment, and third-party
disambiguation agents were all built from one shared
TrackerAgentsConfig fed by a single tracker-mapping config slot. That
forced a single AgentTimeout to be reused and patched per worker, and
two unrelated max-turns fields to share one struct.

Split the in-code config into TrackerMappingAgentConfig,
TrackerEnrichmentAgentConfig, and DisambiguationAgentConfig, each with
its own timeout and max-turns, and add dedicated tracker-enrichment and
third-party-disambiguation provider slots (the latter resolving next to
third-party-vetter). Enrichment and disambiguation fall back to the
tracker-mapping slot when their own provider is unset, preserving
single-config deployments.

Drop the shared pkg/agentsbuild package and duplicate its small wiring
into probod and proboctl so the two executables stay decoupled. Wire
the new env vars, builder test coverage, and Helm values.

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

pkg/cookiebanner/tracker_mapping_worker.go

@@ -50,12 +50,12 @@ type trackerMappingHandler struct {
 func NewTrackerMappingWorker(
 	pgClient *pg.Client,
 	logger *log.Logger,
-	mappingCfg TrackerAgentsConfig,
-	disambiguationCfg thirdparty.DisambiguationConfig,
+	mappingCfg TrackerMappingAgentConfig,
+	disambiguationCfg thirdparty.DisambiguationAgentConfig,
 	staleAfter time.Duration,
 	opts ...worker.Option,
 ) *worker.Worker[coredata.TrackerPattern] {
-	agentTimeout := mappingCfg.AgentTimeout
+	agentTimeout := mappingCfg.Timeout
 	if agentTimeout <= 0 {
 		agentTimeout = defaultAgentTimeout
 	}