fix: prepend claude CLI install paths to subprocess PATH (env-sanitizer)

Root cause: worker launched by Claude Desktop inherits a narrow PATH that
omits ~/.local/bin and ~/.bun/bin, so SDK subprocesses fail with
"Claude executable not found" — observations pile up in the queue but
are never processed, producing the "only my messages get recorded"
symptom that patching session reset logic could not fix.

env-sanitizer now prepends the common install locations (~/.local/bin,
~/.bun/bin, ~/bin, /opt/homebrew/bin, /usr/local/bin on Unix; matching
Windows locations) to PATH before spawning SDK subprocesses, so the
worker can locate the claude binary regardless of launch context.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/supervisor/env-sanitizer.ts

@@ -12,6 +12,35 @@ export const ENV_PRESERVE = new Set([
   'CLAUDE_CODE_GIT_BASH_PATH',
 ]);
 
+/**
+ * Common user-install locations where the `claude` CLI binary may live.
+ * Claude Desktop spawns the worker without inheriting the user's shell profile
+ * PATH, so `~/.local/bin` and `~/.bun/bin` are frequently missing — which
+ * causes the SDK subprocess to fail with "Claude executable not found" and
+ * silently blocks all memory processing.
+ *
+ * We unconditionally prepend these paths (skipping ones already present) so
+ * the worker can locate `claude` regardless of how it was launched.
+ */
+function extraClaudePathLocations(env: NodeJS.ProcessEnv): string[] {
+  const home = env.HOME || env.USERPROFILE;
+  if (!home) return ['/opt/homebrew/bin', '/usr/local/bin'];
+  if (process.platform === 'win32') {
+    return [
+      `${home}\\AppData\\Local\\Programs\\claude`,
+      `${home}\\.bun\\bin`,
+      `${home}\\.local\\bin`
+    ];
+  }
+  return [
+    `${home}/.local/bin`,
+    `${home}/.bun/bin`,
+    `${home}/bin`,
+    '/opt/homebrew/bin',
+    '/usr/local/bin'
+  ];
+}
+
 export function sanitizeEnv(env: NodeJS.ProcessEnv = process.env): NodeJS.ProcessEnv {
   const sanitized: NodeJS.ProcessEnv = {};
 
@@ -23,5 +52,15 @@ export function sanitizeEnv(env: NodeJS.ProcessEnv = process.env): NodeJS.Proces
     sanitized[key] = value;
   }
 
+  // Ensure PATH includes common locations where `claude` CLI is installed.
+  // See extraClaudePathLocations() for the rationale.
+  const sep = process.platform === 'win32' ? ';' : ':';
+  const currentPath = sanitized.PATH || sanitized.Path || '';
+  const existing = new Set(currentPath.split(sep).filter(Boolean));
+  const toPrepend = extraClaudePathLocations(env).filter(p => !existing.has(p));
+  if (toPrepend.length > 0) {
+    sanitized.PATH = [...toPrepend, currentPath].filter(Boolean).join(sep);
+  }
+
   return sanitized;
 }