feedkit: ergonomics pass (shared logger, route compiler, param helpers)

- Add logging.Logf as the canonical printf-style logger type used across feedkit.
  - Update scheduler and dispatch to alias their Logger types to logging.Logf.
  - Eliminates type-mismatch friction when wiring one log function through the system.

- Add dispatch.CompileRoutes(*config.Config) ([]dispatch.Route, error)
  - Compiles config routes into dispatch routes with event.ParseKind normalization.
  - If routes: is omitted, defaults to “all sinks receive all kinds”.

- Expand config param helpers for both SourceConfig and SinkConfig
  - Add ParamBool/ParamInt/ParamDuration/ParamStringSlice (+ Default variants).
  - Supports common YAML-decoded types (bool/int/float/string, []any, etc.)
  - Keeps driver code cleaner and reduces repeated type assertions.

- Fix Postgres sink validation error prefix ("postgres sink", not "rabbitmq sink").

sinks/postgres.go

@@ -29,7 +29,7 @@ func (p *PostgresSink) Consume(ctx context.Context, e event.Event) error {
 	// Boundary validation: if something upstream violated invariants,
 	// surface it loudly rather than printing partial nonsense.
 	if err := e.Validate(); err != nil {
-		return fmt.Errorf("rabbitmq sink: invalid event: %w", err)
+		return fmt.Errorf("postgres sink: invalid event: %w", err)
 	}
 
 	// TODO implement Postgres transaction