Reconcile the env-var contract (kill dead AZURE_AI_*, fix double-path)

[dkirby-ms]

Summary

.env advertises AZURE_AI_ENDPOINT/KEY/DEPLOYMENT/API_VERSION that no code reads, and .env:65 shows OPENAI_LLM_ENDPOINT=…/v1/chat/completions, which double-appends the path because the transport adds /v1/chat/completions itself (llm-client.ts:206). This is a latent misconfiguration trap and misleading documentation. Make the env contract match reality.

Scope / Tasks

• Remove the dead AZURE_AI_* block from .env:59-62 (or, if Issue 3 chose to implement them, wire them in config.ts and document precedence — pick one, do not leave them dead).
• Fix .env:65 to the base-URL form (https://api.openai.com) matching .env.example:62 so the transport's appended path is correct.
• Audit .env.example and any deploy docs for the same trap; add an inline comment that the endpoint must be the base URL.
• grep-confirm no remaining references to AZURE_AI_* in code/docs after change.

Acceptance Criteria

• grep -rn AZURE_AI packages/ .env returns nothing dead (either removed or genuinely consumed).
• .env and .env.example agree on the base-URL form; no /v1/chat/completions suffix in the endpoint value.
• A short note in env docs explains the endpoint format and the append behavior.

Dependencies

none (can land early); coordinate with #511 if AZURE_AI is implemented.

Size

S

Derived from the LLM narration gap analysis (Volo) and decomposition (Elminster).