Overhaul Feynman harness: streamline agents, prompts, and extensions

Remove legacy chains, skills, and config modules. Add citation agent,
SYSTEM.md, modular research-tools extension, and web-access layer.
Add ralph-wiggum to Pi package stack for long-running loops.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/config/paths.ts

@@ -22,10 +22,6 @@ export function getDefaultSessionDir(home = getFeynmanHome()): string {
 	return resolve(home, "sessions");
 }
 
-export function getFeynmanConfigPath(home = getFeynmanHome()): string {
-	return resolve(home, "config.json");
-}
-
 export function getBootstrapStatePath(home = getFeynmanHome()): string {
 	return resolve(getFeynmanStateDir(home), "bootstrap.json");
 }