Move Firecrawl API key from top-level config into Agents.Tools

Firecrawl is a tool used by agents (tracker mapping, third-party
assessor), so its configuration belongs under AgentsConfig rather than
as a standalone Config field. Adds AgentToolsConfig to hold agent tool
credentials and updates all config propagation consumers.

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

pkg/bootstrap/builder.go

@@ -176,9 +176,6 @@ func (b *Builder) Build() (*probodconfig.FullConfig, error) {
 					CacheTTL:       b.getEnvIntOrDefault("WEBHOOK_CACHE_TTL", 86400),
 				},
 			},
-			Firecrawl: probodconfig.FirecrawlConfig{
-				APIKey: b.getEnv("FIRECRAWL_API_KEY"),
-			},
 			Agents: probodconfig.AgentsConfig{
 				Providers: map[string]probodconfig.LLMProviderConfig{
 					"openai": {
@@ -214,6 +211,9 @@ func (b *Builder) Build() (*probodconfig.FullConfig, error) {
 					Temperature: b.getEnvFloatPtr("AGENT_TRACKER_MAPPING_TEMPERATURE"),
 					MaxTokens:   b.getEnvIntPtr("AGENT_TRACKER_MAPPING_MAX_TOKENS"),
 				},
+				Tools: probodconfig.AgentToolsConfig{
+					FirecrawlAPIKey: b.getEnv("FIRECRAWL_API_KEY"),
+				},
 			},
 			CustomDomains: probodconfig.CustomDomainsConfig{
 				RenewalInterval:   b.getEnvIntOrDefault("CUSTOM_DOMAINS_RENEWAL_INTERVAL", 3600),