grok: fix xsearch (multi-agent web_search), pin grok-build, RTFM doc sweep

Root-caused the long-standing `ask-grok.sh xsearch` "no result (stopReason=)"
failure by reading Grok's bundled docs (~/.grok/docs/user-guide + README) instead
of probing:
- web_search runs a SEPARATE multi-agent model (grok-4.20-multi-agent), so the
  wrapper's blanket --no-subagents strangled it -> indefinite hang, 0 bytes. Scoped
  --no-subagents OFF xsearch; use --yolo (documented headless tool-run posture).
- xsearch prompt mandated X/Twitter search on every call (slow multi-agent) and the
  budget was 240s -> still timed out. Now web-primary (X only when relevant), 300s.
  Validated end-to-end through the wrapper: 23s, correct answer + 3 sources.

Model: pin -m grok-build (xAI flagship, 512k, the documented default) for the
reasoning modes (text/verify/review*) so quality is deterministic and not at the
mercy of the runtime default (this machine drifted to grok-composer-2.5-fast, a fast
Cursor coding model). xsearch + image/video keep the runtime default. Validated text
mode on grok-build (13s).

Doc accuracy (SKILL.md): corrected the model facts (default, the separate web_search
model, --effort unsupported on grok-build per supports_reasoning_effort:false);
documented the xsearch subagent exception. Fixed a stale in-script comment claiming
--rules/--disallowed-tools "tripped the CLI" (both are valid headless flags).

memory: add feedback_interview_ai_read_docs (read bundled docs / interview the model
before probing) + index; errorlog correction.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.claude/memory/MEMORY.md

@@ -55,6 +55,7 @@
 - [Point vault-access teammates at SOPS path](feedback_vault_pointer_for_teammates.md) — When relaying infra/credential info to Howard or other vault-access teammates, hand over the SOPS path + key anchors; don't transcribe the entry's fields into the message.
 - [/tmp path mismatch on Windows](feedback_tmp_path_windows.md) — Write tool and Git Bash resolve `/tmp` to DIFFERENT real dirs. Use heredoc or workspace path for JSON payloads handed to curl.
 - [Windows strips embedded double-quotes](feedback_windows_quote_stripping.md) — Embedded `"` in an arg gets eaten twice over: PowerShell->curl.exe (CommandLineToArgvW) AND RMM->cmd.exe. Use single-quoted heredoc `<<'JSON'` + `--data-binary @-` for bodies; build `"` from `[char]34`; or drop the quoted part (e.g. `shutdown /c`).
+- [Interview the AI / read its docs before probing](feedback_interview_ai_read_docs.md) — To learn an external AI/CLI's syntax or capabilities, READ its bundled docs (Grok: `~/.grok/docs/user-guide/`, `README.md`, `grok inspect`/`models`/`--help`) or interview the model; don't guess flags or run slow trial-and-error. One run to confirm a doc-derived hypothesis, not a dozen to discover.
 - [Windows bash command mapping](feedback_windows_bash_mapping.md) — `bash` often resolves to WSL stub instead of Git/MSYS bash required by the harness. Fix by prepending `C:\Program Files\Git\bin` (and usr\bin) to PATH, or source `.claude/scripts/ensure-git-bash.ps1`. Profile has the logic; use plain `bash .claude/scripts/...` after remap. See the helper and this memory file for details.
 - [Git must authenticate non-interactively](feedback_git_noninteractive_auth.md) — Mike's gripe with Git for Windows is the constant password prompts (GCM) that hang automation, NOT the tool itself. D:\ClaudeTools is set to `credential.helper=store` primed with the azcomputerguru Gitea API token (host 172.16.3.20:3000); always set `GIT_TERMINAL_PROMPT=0`. Any never-prompts solution is acceptable.
 - [Vault git auth — GCM shadows store token](feedback_vault_gcm_shadow_auth.md) — vault sync "Failed to authenticate user" on git.azcomputerguru.com: GCM is first in the helper chain and shadows the valid store token. Fix (machine-local): store-only credential.helper reset + pin `azcomputerguru@` in the vault remote URL so store returns the durable PAT (not the volatile OAUTH_USER JWT). Applied GURU-5070 2026-06-07.