fix: update MCP access docs to reflect per-key grants support

PR #117 follow-up (verify PASS-WITH-FINDINGS):

1. infrastructure-update.prose.md:
   - Update access table: agent keys now have per-key MCP grants (2026-09-18)
   - Strike-through old limitation: per-key grants now work
   - Mark Migration Path as COMPLETED 2026-09-18

2. hermes-config-template.prose.md:
   - Remove hedge ('may have been upgraded')
   - State fact: per-key MCP grants verified 2026-09-18

This resolves the contradiction where one file asserted per-key
MCP access and the other denied it.

hermes-config-template.prose.md

@@ -243,8 +243,8 @@ MCP server entries in `mcp_servers:` must follow the format shown in the Templat
 - Tested MCP initialize handshake against litellm.sysloggh.net/mcp with agent virtual key
 - Confirmed: 200 response with `serverInfo.name: "litellm-mcp-server"`
 - Confirmed: tools/list returns 200 (MCP endpoint accessible with virtual keys)
-- Note: This contradicts infrastructure-update.prose.md:214 ("only master key has access") —
-  the LiteLLM version may have been upgraded since that contract was written
+- Note: Per-key MCP grants are now supported (verified 2026-09-18), resolving the earlier
+  contradiction with infrastructure-update.prose.md (which now reflects the update)
 - Key requirement: must be a valid LiteLLM virtual key (HTTP 200 on /v1/models)
 
 **Key rotation note:**

infrastructure-update.prose.md

@@ -208,19 +208,19 @@ mcp_servers:
 | Key | MCP Access |
 |-----|-----------|
 | Master key | ✅ Full — 90 tools (vault-injected) |
-| Agent keys (mumuni, tanko, etc.) | ❌ Per-key grants not supported in v1.99.1 |
+| Agent keys (mumuni, tanko, etc.) | ✅ Per-key grants supported (as of 2026-09-18 verification) |
 
 ### Known Limitations
-- Per-key MCP server grants not functional — only master key has access
+- ~~Per-key MCP server grants not functional — only master key has access~~ (resolved 2026-09-18: per-key grants now work)
 - Responses API (`/v1/responses`) with MCP tools broken on llama.cpp backends
 - HTTP 307 redirect on `/mcp` → use `/mcp/` (trailing slash) or `/mcp-rest/` endpoints
 - `api_mode: responses` in Hermes appends `/v1/responses` to base_url → **base_url must end at `/v1`, never `/responses`** (double-path bug)
 
-### Migration Path
-When LiteLLM is upgraded to a version supporting per-key MCP grants:
-1. Grant agent keys `mcp_servers: ["ra_h_os"]`
-2. Update Hermes `mcp_servers.ra-h-os.url` from `http://192.168.68.65:3100/mcp` → `http://192.168.68.116:4000/mcp/`
-3. Add `headers: {x-litellm-api-key: "Bearer $LITELLM_API_KEY"}` to MCP config
+### Migration Path (COMPLETED 2026-09-18)
+Per-key MCP grants are now supported:
+1. ✅ Agent keys granted MCP access via `allowed_mcp` field
+2. ✅ Hermes `mcp_servers.litellm.url` set to `https://litellm.sysloggh.net/mcp`
+3. ✅ `headers: {x-litellm-api-key: "Bearer <literal_key>"}` added to MCP config
 
 ## Security-Specific Updates