PRD 0062: supervisor override for egress token blocks

When the outbound DLP catches a token, route the block through the
existing supervisor approval queue instead of returning 403 outright.
The egress proxy holds the request open until the operator answers, then
remembers an approved value for the life of the proxy so the request --
and later ones carrying it -- flow through. Fails closed on rejection,
timeout, malformed response, or when supervise is disabled.

- ScanResult.matched carries the raw matched substring (sidecar-only;
  never logged or written to the proposal). scan_outbound and the token
  detectors take a safe_tokens set and skip approved values, continuing
  past a safelisted match so a second secret in the same request is
  still caught.
- New egress-token-allow proposal tool, written directly to the queue by
  the addon (the gitleaks-allow pattern from PRD 0061). build_token_allow
  _payload renders host/method/path/detector reason + redacted context.
- Async request hook polls the queue without stalling the proxy event
  loop; EGRESS_TOKEN_ALLOW_TIMEOUT_SECONDS (default 300) bounds the wait.
- Supervisor TUI renders egress-token-allow like gitleaks-allow: report
  only, modify unavailable, approval requires a recorded reason.
- Unit tests for the matched/safe-tokens plumbing, payload builder, tool
  constant round-trip, and TUI paths; README + PRD 0062.

Closes #261.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HnvBjPZC5V7qeQpFbQdDmS

README.md

@@ -15,6 +15,7 @@
 ## Features
 
 - **Per-bottle egress allowlist** — TLS-bumped HTTP/HTTPS chokepoint with a per-manifest host allowlist; per-route path/method/header `matches` filtering; outbound DLP scanning for known tokens and secrets, inbound DLP scanning for prompt-injection attempts; DoH and arbitrary hosts blocked by default.
+- **Supervisor override for token blocks** — when the outbound DLP catches a token, the request is held and surfaced in `./cli.py supervise` instead of failing outright. The operator approves or rejects; an approved value is remembered for the life of the egress proxy so the request — and later ones carrying it — flow through. Fails closed on rejection or timeout.
 - **Tokens the agent never sees** — host secrets live in a sidecar; the agent dials `http://sidecar:9099/<path>` and the proxy strips inbound `Authorization` and injects the real token before forwarding. `printenv` in the agent shows proxy URLs only.
 - **Gitleaks-scanned push (git-gate)** — `bottle.git` remotes route through a per-bottle `git daemon` that gitleaks-scans incoming refs pre-receive and forwards clean refs upstream over SSH. The agent never holds the upstream credential.
 - **Manifest-scoped skills + secrets** — each bottle declares its skills, env, git identity, remotes, and egress routes; unknown keys die at load.
@@ -150,6 +151,8 @@ You help maintain Gitea-hosted projects.
 | `dlp.inbound_detectors` | no | `false` disables inbound scanning; list restricts to named detectors (`naive_injection_detection`). |
 | `git.fetch` | no | `true` permits smart HTTP clone/fetch (`git-upload-pack`) for this host. Push (`git-receive-pack`) remains blocked. |
 
+When an outbound request is blocked because a DLP detector matched a token, the proxy queues an `egress-token-allow` proposal for the operator's `./cli.py supervise` TUI and holds the request open until it is answered (or `EGRESS_TOKEN_ALLOW_TIMEOUT_SECONDS`, default 300s, elapses — after which it fails closed). The operator never sees the raw token, only the host, method, path, and a redacted snippet. Approving adds the value to an in-memory safelist for the life of the egress proxy. Structural blocks (CRLF injection) and not-in-allowlist host blocks stay hard `403`s.
+
 More examples in `examples/`. Full design lives under `docs/prds/`; the trust-boundary rationale is in `docs/prds/0011-per-file-md-manifest.md`.
 
 ## Trademarks