fix(redfix): gitignore config.json (F-redfix-2 remedy) + consume BUILDER-INBOX

Adversary finding F-redfix-2 (non-blocking): config.json sits untracked AND
un-gitignored at both Builder clone roots holding a live-shaped Tinfoil API key
(.provider.tinfoil.options.apiKey) -- one `git add -A` from being pushed to
git.autonomic.zone. Independently re-verified all four claims from my own clone:
untracked, never committed (git log --all -- config.json empty), not ignored,
key live-shaped. Latent risk, NOT an existing leak.

Remedy: add config.json to the "local secrets / env -- never commit" block.
Proved effective by replaying `git add -A` against a scratch GIT_INDEX_FILE:
config.json is no longer staged (only .gitignore, main.go).

Did not delete/move config.json (foreign file, not created by this loop), did
not rotate the key (operator's call -- escalated), did not gitignore main.go
(foreign, but no secret in it), did not reopen redfix or touch REVIEW-redfix.md.
Phase redfix stays DONE; only the Adversary closes F-redfix-2, after re-test.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018nVVSxRnj3K5MxGGRJzvTe

.gitignore

@@ -3,6 +3,8 @@
 *.key
 *.pem
 !docs/**/*.pem
+# holds a live provider API key at .provider.tinfoil.options.apiKey (F-redfix-2)
+config.json
 # python
 __pycache__/
 *.pyc