C4 follow-up: re-record manager fixture post-C4, strip bash leftover from SOP, document remaining asks as C4-followup proposal

Closes review asks from cross-review of C4:

- Jobs ask #2: team-building.en.md still referenced the bash+fetch
  pattern for goal creation. Rewritten as a deferred-tool note pointing
  to C5 follow-up, without re-teaching the HTTP shape C4 just removed.

- Karpathy ask #1 (partial): re-recorded manager-task-handoff against
  main to produce post-C4 positive evidence. VP Engineering has
  hire_agent available via canRequestHire, but when directed NOT to
  hire, the recorded trace shows task decomposition only (no
  hire_agent invocation). 455 in / 769 out tokens; assertions updated
  to pin /api/task/create + agent_ic_ slugs + p99 substring + max 3
  turns. The `non-ceo-dm-reply` re-record is deferred to the follow-up
  ticket.

- Karpathy asks #2, #3, #4 + Jobs asks #1, #3, #4: documented in
  docs/proposals/C4-followup.md with concrete completion criteria.
  Scope covers canFileCeoStrategy predicate, non-ceo-dm-reply
  re-record, RFC 8594 Deprecation/Sunset headers + counter, and a
  negative substring assertion kind for the eval harness.

Eval still green at 8/8. C4 main batch (e2c839b..8e99e01) stands
unchanged; this commit is pure follow-up groundwork.

src/main/prompt-builder/ceo-modes/team-building.en.md

@@ -47,24 +47,7 @@ The filesystem analysis (ls, cat README, skim config) is optional — only run i
 
 ## If no active goal exists
 
-File one goal first, then return to the hire block above in the same wake. Goal creation is **not** yet exposed as an internal tool — use the `bash` tool to POST:
-
-```javascript
-await fetch(`${process.env.AGENT_COMPANY_API_URL}/api/companies/{{companyId}}/goals`, {
-  method: "POST",
-  headers: {
-    "Authorization": `Bearer ${process.env.AGENT_COMPANY_API_KEY}`,
-    "Content-Type": "application/json; charset=utf-8",
-    "X-Agent-Company-Run-Id": "{{runId}}"
-  },
-  body: JSON.stringify({
-    title: "<goal>",
-    description: "<measurable success criteria>",
-    ownerAgentId: "{{agentId}}",
-    status: "active"
-  })
-});
-```
+File one goal first, then return to the hire block above in the same wake. Goal creation is not yet exposed as an internal tool; this will be addressed in the C5-follow-up ("expose remaining CEO primitives as tools"). Until that lands, this document will not re-teach the HTTP+bash path that C4 removed — if the harness cannot provide a goal through system state, that is a bootstrap bug and should be reported to the operator rather than worked around in the LLM surface.
 
 ## Self-assignment is rejected