docs(research): mark credential-proxy note as implemented (agents get placeholders)

The note still described the pre-gateway state as "today" — raw provider
tokens env-injected into the agent, readable via printenv — which is no longer
true and was actively misleading. Add a dated Status banner and flag the stale
"today's wiring" / "recommended path forward" passages: the agent now holds only
a placeholder (e.g. CLAUDE_CODE_OAUTH_TOKEN=egress-placeholder) and the real
token is injected as the upstream Authorization header by the existing
pipelock/mitmproxy egress sidecar (EgressRoute auth_scheme + token_ref, one MITM
not two), generalized across Claude/Codex/Pi and git-host tokens. Reasoning
preserved per the research-note convention.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LhiafsABCr46bu3oHUm7wa

docs/research/agent-credential-proxy-landscape.md

@@ -15,6 +15,25 @@ the biggest credential risk).
 
 ## Summary
 
+> **Status — implemented (2026-07-14).** This note's recommendation
+> shipped, so the "today" / "in-flight" tenses below are now historical
+> (kept as the reasoning that led here). Current reality: bot-bottle no
+> longer injects raw provider tokens into the agent. The agent's environ
+> carries only a **placeholder** (e.g.
+> `CLAUDE_CODE_OAUTH_TOKEN=egress-placeholder`); the real token is held
+> in the egress sidecar and injected as the upstream `Authorization`
+> header. Rather than adding a *separate* in-container reverse proxy (as
+> proposed below), credential injection was folded into the **existing
+> pipelock/mitmproxy egress firewall**: an `EgressRoute` carries
+> `auth_scheme` + `token_ref`, the host token is forwarded into the
+> sidecar addon under an `EGRESS_TOKEN_N` slot, and the addon rewrites
+> `Authorization` on matching routes — **one MITM, not two** (this
+> resolves the Infisical-doubling concern noted later). The same
+> mechanism now covers Codex and Pi provider tokens and git-host PATs.
+> A `printenv` inside the bottle yields the placeholder, not the secret.
+> For current wiring see `bot_bottle/egress.py` and
+> `bot_bottle/contrib/*/agent_provider.py`.
+
 Today every bot-bottle agent gets `CLAUDE_CODE_OAUTH_TOKEN` (and
 any `bottle.env` secrets like a Gitea PAT) injected as env vars,
 which means the agent process can read them with `printenv` or
@@ -95,7 +114,9 @@ The remaining credible designs reduce to three:
 
 ### Anthropic / Claude Code
 
-**Today's wiring** (`bot_bottle/cli/start.py`): the host's
+**Original wiring** (pre-gateway; **superseded 2026-07-14** — see the
+Status note in the Summary; the token now lives in the egress sidecar
+and the agent gets a placeholder): the host's
 `BOT_BOTTLE_CLAUDE_OAUTH_TOKEN` is forwarded into the bottle as
 `CLAUDE_CODE_OAUTH_TOKEN` via `docker run -e CLAUDE_CODE_OAUTH_TOKEN`
 (no `=value`, so the value never lands on argv — good). Inside the
@@ -332,6 +353,12 @@ exposed.
 
 ## Recommended path forward
 
+> **Mostly implemented (2026-07-14).** Steps 1–3 shipped — the token
+> injection moved into the egress sidecar (folded into pipelock rather
+> than a standalone reverse proxy) and generalized to Codex/Pi/git-host
+> tokens. Steps 4–5 (issuance-side scope narrowing, per-route allowlists)
+> remain good hygiene. See the Status note in the Summary.
+
 In priority order:
 
 1. **In-container reverse proxy holding `CLAUDE_CODE_OAUTH_TOKEN`.**